refactor(plan_node_fmt): slightly generalize the fmt of join-related nodes

[ice1000]

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What's changed and what's your intention?

This is a follllow up of #10132, #10155, #10157.

Checklist For Contributors

• Yes

Documentation

• My PR DOES NOT contain user-facing changes.

[codecov]

Codecov Report

Merging #10253 (9249f44) into main (d695fa6) will decrease coverage by 0.03%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##             main   #10253      +/-   ##
==========================================
- Coverage   70.62%   70.59%   -0.03%     
==========================================
  Files        1245     1245              
  Lines      212617   212619       +2     
==========================================
- Hits       150154   150094      -60     
- Misses      62463    62525      +62     

Flag	Coverage Δ
rust	70.59% <50.00%> (-0.03%)	⬇️

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Impacted Files	Coverage Δ
...c/frontend/src/optimizer/plan_node/batch_insert.rs	45.58% <0.00%> (-4.42%)	⬇️
...frontend/src/optimizer/plan_node/generic/insert.rs	61.17% <ø> (ø)
...ntend/src/optimizer/plan_node/batch_lookup_join.rs	53.12% <20.58%> (-9.20%)	⬇️
...rontend/src/optimizer/plan_node/batch_hash_join.rs	78.46% <21.21%> (-12.60%)	⬇️
...nd/src/optimizer/plan_node/stream_temporal_join.rs	61.48% <85.71%> (-1.81%)	⬇️
.../src/optimizer/plan_node/batch_nested_loop_join.rs	82.55% <100.00%> (-1.82%)	⬇️
...c/frontend/src/optimizer/plan_node/logical_join.rs	90.31% <100.00%> (-0.06%)	⬇️
...ntend/src/optimizer/plan_node/stream_delta_join.rs	96.05% <100.00%> (-0.25%)	⬇️
...ontend/src/optimizer/plan_node/stream_hash_join.rs	95.62% <100.00%> (-0.13%)	⬇️
src/frontend/src/optimizer/plan_node/utils.rs	90.32% <100.00%> (+1.03%)	⬆️

... and 4 files with indirect coverage changes

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