feat(frontend): add FilterMerge

[likg227]

What's changed and what's your intention?

This pr does what the title said. Because we may split one LogicalFilter into multiple LogicalFilters using some rules(e.g. FilterJoin) and push them down, there may be a LogicalFilter directly on top of another LogicalFilter. To deal with it, I use a simple rule to merge them thus improving the optimization.

Checklist

• I have written necessary docs and comments
• I have added necessary unit tests and integration tests

Refer to a related PR or issue link (optional)

split from #1979

[codecov]

Codecov Report

Merging #2007 (0e96a5a) into main (83efe76) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2007      +/-   ##
==========================================
+ Coverage   70.77%   70.79%   +0.02%     
==========================================
  Files         627      628       +1     
  Lines       80806    80803       -3     
==========================================
+ Hits        57187    57205      +18     
+ Misses      23619    23598      -21     

Flag	Coverage Δ
rust	70.79% <100.00%> (+0.02%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...rontend/src/optimizer/plan_node/logical_project.rs	97.53% <ø> (ø)
src/frontend/src/optimizer/mod.rs	93.78% <100.00%> (+0.03%)	⬆️
src/frontend/src/optimizer/rule/filter_merge.rs	100.00% <100.00%> (ø)
...src/optimizer/rule/pull_up_correlated_predicate.rs	98.73% <100.00%> (-0.02%)	⬇️
src/meta/src/manager/stream_clients.rs	88.88% <0.00%> (-7.41%)	⬇️
src/batch/src/executor/fuse.rs	94.20% <0.00%> (-4.35%)	⬇️
src/meta/src/barrier/command.rs	56.07% <0.00%> (-2.81%)	⬇️
src/meta/src/barrier/mod.rs	69.00% <0.00%> (-1.07%)	⬇️
src/meta/src/hummock/hummock_manager.rs	91.23% <0.00%> (-0.11%)	⬇️
src/meta/src/barrier/info.rs	100.00% <0.00%> (ø)
... and 6 more

📣 Codecov can now indicate which changes are the most critical in Pull Requests. Learn more

[xiangjinwu]

Could you elaborate why is this an improvement over the original FilterProject?

[likg227]

Sorry, I misunderstand the original implementation of FilterProject. I will fix it.