[DOP-13840] - add JSON.parse_column and JSON.serialize_column methods

[maxim-lixakov]

Change Summary

• Add JSON.parse_column and JSON.serialize_column methods to facilitate direct parsing of JSON strings into Spark DataFrame columns and serialization of structured DataFrame columns back into JSON strings.
• Update following tests and documentation

Related issue number

Checklist

• Commit message and PR title is comprehensive
• Keep the change as small as possible
• Unit and integration tests for the changes exist
• Tests pass on CI and coverage does not decrease
• Documentation reflects the changes where applicable
• docs/changelog/next_release/<pull request or issue id>.<change type>.rst file added describing change
  (see CONTRIBUTING.rst for details.)
• My PR is ready to review.

[codecov]

Codecov Report

Attention: Patch coverage is 87.50000% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 94.39%. Comparing base (511a330) to head (315478f).

❗ Current head 315478f differs from pull request most recent head 5976497. Consider uploading reports for the commit 5976497 to get more accurate results

Files	Patch %	Lines
onetl/file/format/json.py	87.50%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #257      +/-   ##
===========================================
- Coverage    94.39%   94.39%   -0.01%     
===========================================
  Files          204      204              
  Lines         7910     7926      +16     
  Branches      1402     1404       +2     
===========================================
+ Hits          7467     7482      +15     
  Misses         318      318              
- Partials       125      126       +1     

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