chore: add compatible notice for old row format syntax

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What's changed and what's your intention?

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

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Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[codecov]

Codecov Report

Merging #12373 (c95ae42) into main (71d9b0b) will increase coverage by 0.01%.
Report is 2 commits behind head on main.
The diff coverage is 68.18%.

@@            Coverage Diff             @@
##             main   #12373      +/-   ##
==========================================
+ Coverage   69.86%   69.87%   +0.01%     
==========================================
  Files        1419     1419              
  Lines      235829   235832       +3     
==========================================
+ Hits       164757   164787      +30     
+ Misses      71072    71045      -27     

Flag	Coverage Δ
rust	69.87% <68.18%> (+0.01%)	⬆️

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

Files Changed	Coverage Δ
src/frontend/src/handler/mod.rs	58.58% <40.00%> (-0.93%)	⬇️
src/sqlparser/src/ast/statement.rs	43.09% <40.00%> (-0.10%)	⬇️
src/frontend/src/handler/create_source.rs	48.46% <75.00%> (+<0.01%)	⬆️
src/frontend/planner_test/src/lib.rs	87.31% <100.00%> (+0.02%)	⬆️
src/frontend/src/handler/alter_table_column.rs	69.29% <100.00%> (ø)
src/frontend/src/handler/explain.rs	79.19% <100.00%> (-0.24%)	⬇️

... and 9 files with indirect coverage changes

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