feat: add missing columns in information_schema.columns and add current_setting func

[yezizp2012]

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What's changed and what's your intention?

To support golang ORM library 'xorm' and for grafana, this PR adds some missing columns in information_schema.columns, add a current_setting function and fixes several issues.
Related #10131 , #10134 . Resolve #10051 .

Checklist For Contributors

• 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).
• I have demonstrated that backward compatibility is not broken by breaking changes and created issues to track deprecated features to be removed in the future. (Please refer to the issue)
• All checks passed in ./risedev check (or alias, ./risedev c)

Checklist For Reviewers

• I have requested macro/micro-benchmarks as this PR can affect performance substantially, and the results are shown.

Documentation

• My PR DOES contain user-facing changes.

Click here for Documentation

Types of user-facing changes

Please keep the types that apply to your changes, and remove the others.

• SQL commands, functions, and operators

Release note

1. add some missing columns in information_schema.columns: column_default, character_maximum_length and udt_name.
2. add a new sql function: current_setting.

[codecov]

Codecov Report

Merging #10269 (fa1d089) into main (dd5c41b) will increase coverage by 0.05%.
The diff coverage is 41.79%.

@@            Coverage Diff             @@
##             main   #10269      +/-   ##
==========================================
+ Coverage   70.54%   70.59%   +0.05%     
==========================================
  Files        1243     1243              
  Lines      212793   212860      +67     
==========================================
+ Hits       150119   150277     +158     
+ Misses      62674    62583      -91     

Flag	Coverage Δ
rust	70.59% <41.79%> (+0.05%)	⬆️

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

Impacted Files	Coverage Δ
src/common/src/types/postgres_type.rs	15.09% <0.00%> (-3.96%)	⬇️
...c/catalog/system_catalog/information_schema/mod.rs	0.00% <0.00%> (ø)
src/frontend/src/binder/expr/function.rs	85.92% <63.15%> (-0.55%)	⬇️
src/common/src/session_config/mod.rs	62.82% <71.42%> (+29.33%)	⬆️
src/frontend/src/binder/mod.rs	90.50% <100.00%> (+0.32%)	⬆️

... and 3 files with indirect coverage changes

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[wangrunji0408]

LGTM