[Fix #385] Disable Performance/BlockGivenWithExplicitBlock by default

See linked issue for benchmark details. I tested with YJIT and its even worse: ``` ruby 3.4.0dev (2024-09-05T09:43:46Z master 63cbe3f6ac) +YJIT [x86_64-linux] Warming up -------------------------------------- block 1.635M i/100ms block w/ block 285.930k i/100ms block_given? 1.867M i/100ms block_given? w/ block 1.497M i/100ms Calculating ------------------------------------- block 22.611M (±12.7%) i/s (44.23 ns/i) - 111.180M in 5.033721s block w/ block 3.034M (± 8.5%) i/s (329.59 ns/i) - 15.154M in 5.032609s block_given? 24.935M (±10.7%) i/s (40.10 ns/i) - 123.254M in 5.002983s block_given? w/ block 23.007M (±14.7%) i/s (43.47 ns/i) - 113.782M in 5.058213s Comparison: block_given?: 24935388.3 i/s block_given? w/ block: 23006920.5 i/s - same-ish: difference falls within error block: 22610939.8 i/s - same-ish: difference falls within error block w/ block: 3034047.2 i/s - 8.22x slower ```
rubocop · Sep 13, 2024 · 8907a12 · 8907a12
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diff --git a/changelog/change_disable_block_given.md b/changelog/change_disable_block_given.md
@@ -0,0 +1 @@
+* [#385](https://github.com/rubocop/rubocop-performance/issues/385): Disable `Performance/BlockGivenWithExplicitBlock` by default. ([@earlopain][])
diff --git a/config/default.yml b/config/default.yml
@@ -32,8 +32,11 @@ Performance/BindCall:
 
 Performance/BlockGivenWithExplicitBlock:
   Description: 'Check block argument explicitly instead of using `block_given?`.'
-  Enabled: pending
+  # This cop was created due to a mistake in microbenchmark.
+  # https://github.com/rubocop/rubocop-performance/issues/385
+  Enabled: false
   VersionAdded: '1.9'
+  VersionChanged: <<next>>
 
 Performance/Caller:
   Description: >-

diff --git a/lib/rubocop/cop/performance/block_given_with_explicit_block.rb b/lib/rubocop/cop/performance/block_given_with_explicit_block.rb
@@ -6,6 +6,9 @@ module Performance
       # Identifies unnecessary use of a `block_given?` where explicit check
       # of block argument would suffice.
       #
+      # NOTE: This cop produces code with significantly worse performance when a
+      # block is being passed to the method and as such should not be enabled.
+      #
       # @example
       #   # bad
       #   def method(&block)