[DOP-22431] Improve Excel documentation

[dolfinus]

Change Summary

Previously Excel class documentation only noted that options are documented elsewhere. Now all of them are documented, included to constructor signature and can be recommended by IDE.
Almost all option values are None, and excluded from class repr.

Before:
https://onetl.readthedocs.io/en/0.13.3/file_df/file_formats/excel.html

After:
https://onetl--356.org.readthedocs.build/en/356/file_df/file_formats/excel.html

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 93.33333% with 3 lines in your changes missing coverage. Please review.

Project coverage is 92.47%. Comparing base (86fdd00) to head (3e7c342).
Report is 33 commits behind head on develop.

Files with missing lines	Patch %	Lines
onetl/file/format/excel.py	92.85%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #356      +/-   ##
===========================================
- Coverage    92.51%   92.47%   -0.05%     
===========================================
  Files          229      229              
  Lines         9932     9970      +38     
  Branches      1014     1015       +1     
===========================================
+ Hits          9189     9220      +31     
- Misses         557      562       +5     
- Partials       186      188       +2     

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