statistics: compute and store column order correlation with handle

[eurekaka]

What problem does this PR solve?

First step to fix #9067

What is changed and how it works?

• compute order correlations between columns and handle column;
• store this correlation in mysql.stats_histograms, i.e, in a newly added column Correlation;
• update the upgrade logic and show stats_histograms correspondingly;

Check List

Tests

• Unit test

Code changes

• Has persistent data change

Side effects

• Increased code complexity
• Breaking backward compatibility: upgrade logic has been addressed in this PR also.

Related changes

N/A

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@511a80b). Click here to learn what that means.
The diff coverage is 88.33%.

@@           Coverage Diff            @@
##             master   #9315   +/-   ##
========================================
  Coverage          ?   67.4%           
========================================
  Files             ?     373           
  Lines             ?   78557           
  Branches          ?       0           
========================================
  Hits              ?   52953           
  Misses            ?   20846           
  Partials          ?    4758

Impacted Files	Coverage Δ
executor/builder.go	83.79% <ø> (ø)
executor/analyze.go	63.63% <100%> (ø)
statistics/table.go	83.11% <100%> (ø)
statistics/bootstrap.go	75% <100%> (ø)
executor/show_stats.go	89.78% <100%> (ø)
statistics/histogram.go	81.46% <100%> (ø)
session/bootstrap.go	83.43% <100%> (ø)
planner/core/planbuilder.go	49.02% <20%> (ø)
statistics/sample.go	88.88% <92%> (ø)
statistics/builder.go	89.88% <93.33%> (ø)

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[eurekaka]

/run-all-tests

[eurekaka]

/run-all-tests tidb-test=pr/740

[eurekaka]

/run-all-tests tidb-test=pr/740

[eurekaka]

/run-all-tests tidb-test=pr/740

[alivxxx]

LGTM

[qw4990]

LGTM

[eurekaka]

Wait for https://github.com/pingcap/tidb-test/pull/740 to be merged together.