Adopt heaviest subtree fork choice rule (bp #10441)

[mergify]

This is an automated backport of pull request #10441 done by Mergify

Cherry-pick of 2e1d59f has failed:

On branch mergify/bp/v1.2/pr-10441
Your branch is up to date with 'origin/v1.2'.

You are currently cherry-picking commit 2e1d59ff8.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:

	new file:   core/src/bank_weight_fork_choice.rs
	new file:   core/src/fork_choice.rs
	new file:   core/src/heaviest_subtree_fork_choice/fork_choice.rs
	new file:   core/src/heaviest_subtree_fork_choice/mod.rs
	modified:   core/src/lib.rs
	modified:   local-cluster/tests/local_cluster.rs
	modified:   runtime/src/bank.rs
	modified:   runtime/src/epoch_stakes.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)

	both modified:   core/src/consensus.rs
	both modified:   core/src/replay_stage.rs

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[solana-grimes]

💔 Unable to automerge due to CI failure

[solana-grimes]

😱 New commits were pushed while the automerge label was present.

[codecov]

Codecov Report

Merging #10515 into v1.2 will increase coverage by 0.1%.
The diff coverage is 96.3%.

@@           Coverage Diff            @@
##            v1.2   #10515     +/-   ##
========================================
+ Coverage   81.6%    81.7%   +0.1%     
========================================
  Files        293      296      +3     
  Lines      69249    69720    +471     
========================================
+ Hits       56518    57027    +509     
+ Misses     12731    12693     -38