Add CLI examples for DMS Schema Conversion operations

[vluhans]

Add command examples for 34 DMS operations covering Schema Conversion, data providers, instance profiles, and migration projects.

Operations covered:

• cancel-metadata-model-conversion, cancel-metadata-model-creation
• create-data-provider, create-instance-profile, create-migration-project
• delete-data-provider, delete-instance-profile, delete-migration-project
• describe-conversion-configuration, describe-data-providers, describe-extension-pack-associations, describe-instance-profiles, describe-metadata-model, describe-metadata-model-assessments, describe-metadata-model-children, describe-metadata-model-conversions, describe-metadata-model-creations, describe-metadata-model-exports-as-script, describe-metadata-model-exports-to-target, describe-metadata-model-imports, describe-migration-projects
• export-metadata-model-assessment, get-target-selection-rules
• modify-conversion-configuration, modify-data-provider, modify-instance-profile, modify-migration-project
• start-extension-pack-association, start-metadata-model-assessment, start-metadata-model-conversion, start-metadata-model-creation, start-metadata-model-export-as-script, start-metadata-model-export-to-target, start-metadata-model-import

All examples have been tested against the real DMS service and validated with pytest tests/functional/docs/test_examples.py (11756 tests passed).

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.60%. Comparing base (70d3b38) to head (a83ead6).
⚠️ Report is 53 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #10423      +/-   ##
===========================================
+ Coverage    93.42%   93.60%   +0.18%     
===========================================
  Files          211      211              
  Lines        17312    17355      +43     
===========================================
+ Hits         16174    16246      +72     
+ Misses        1138     1109      -29     

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