perf(common): improve equality caching by explicitly invalidating the entry on __del__

[kszucs]

Previously we used a rather complicated mechanism to implement global equality cache for operation nodes involving tricky weak reference tracking registering callbacks to invalidate cache entries.

While this has greatly improved the overall performance of ibis internals we can have a simpler and more lightweight implementation by storing the equality comparison results in a dict[dict[object_id, bool]] data structure which allows us quick lookups and quick deletions. The caching is also specialized to a pair of objects in contrary to the previous WeakCache implementation which supported arbitrary number of key elements requiring multiple iterations over the key tuple.

---------------------------------------------------------------------------- benchmark 'test_bfs': 2 tests -----------------------------------------------------------------------------
Name (time in ms)              Min               Max              Mean            StdDev            Median               IQR            Outliers       OPS            Rounds  Iterations
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_bfs (0653_384b10f)     2.4032 (1.21)     2.7302 (1.14)     2.5057 (1.21)     0.0630 (1.0)      2.4830 (1.21)     0.0666 (1.0)         25;12  399.0923 (0.83)        169           1
test_bfs (NOW)              1.9786 (1.0)      2.3859 (1.0)      2.0748 (1.0)      0.0786 (1.25)     2.0521 (1.0)      0.0939 (1.41)         55;7  481.9678 (1.0)         229           1
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---------------------------------------------------------------------------- benchmark 'test_dfs': 2 tests -----------------------------------------------------------------------------
Name (time in ms)              Min               Max              Mean            StdDev            Median               IQR            Outliers       OPS            Rounds  Iterations
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_dfs (0653_384b10f)     2.3311 (1.18)     2.9268 (1.27)     2.4361 (1.17)     0.0925 (1.34)     2.3920 (1.14)     0.0478 (1.0)         23;25  410.4854 (0.86)        158           1
test_dfs (NOW)              1.9766 (1.0)      2.3061 (1.0)      2.0900 (1.0)      0.0689 (1.0)      2.0892 (1.0)      0.1262 (2.64)        107;0  478.4618 (1.0)         262           1
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------------------------------------------------------------------------------------ benchmark 'test_equality': 2 tests -----------------------------------------------------------------------------------
Name (time in ns)                     Min                 Max                Mean             StdDev              Median                IQR            Outliers  OPS (Mops/s)            Rounds  Iterations
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_equality (0653_384b10f)     488.4580 (3.06)     670.3340 (2.18)     532.9611 (3.12)     14.3697 (2.14)     530.4795 (3.15)     17.6670 (3.26)     2752;186        1.8763 (0.32)      10000        1000
test_equality (NOW)              159.7090 (1.0)      307.0830 (1.0)      171.0032 (1.0)       6.7183 (1.0)      168.4161 (1.0)       5.4170 (1.0)       777;371        5.8478 (1.0)       10000        1000
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------- benchmark 'test_replace_mapping': 2 tests -----------------------------------------------------------------------------
Name (time in ms)                          Min                Max              Mean            StdDev            Median               IQR            Outliers       OPS            Rounds  Iterations
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_replace_mapping (0653_384b10f)     9.3701 (1.11)     10.6236 (1.0)      9.6592 (1.02)     0.2626 (1.0)      9.5760 (1.08)     0.1286 (1.0)           4;5  103.5287 (0.98)         30           1
test_replace_mapping (NOW)              8.4357 (1.0)      28.9518 (2.73)     9.5036 (1.0)      3.4945 (13.31)    8.8787 (1.0)      0.3668 (2.85)          3;3  105.2228 (1.0)          87           1
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

------------------------------------------------------------------------------ benchmark 'test_replace_pattern': 2 tests ------------------------------------------------------------------------------
Name (time in ms)                           Min                Max               Mean            StdDev             Median               IQR            Outliers      OPS            Rounds  Iterations
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
test_replace_pattern (0653_384b10f)     13.3895 (1.10)     32.2786 (1.0)      14.7143 (1.10)     3.2605 (1.0)      14.2861 (1.13)     0.5695 (1.0)           2;2  67.9613 (0.91)         61           1
test_replace_pattern (NOW)              12.2229 (1.0)      34.5245 (1.07)     13.3812 (1.0)      3.3891 (1.04)     12.6136 (1.0)      0.7824 (1.37)          2;2  74.7315 (1.0)          64           1
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