message: Updated CI fix document
  * Add free-form object spec for testing purpose.
  * Revert "Add free-form object spec for testing purpose."
  This reverts commit
  * Updated ci-fix document.
  Added how to run/fix model validation and semantic validation.
  * Combined run locally and fix tips parts.
  * Tweaked link text.
diff: @@ -23,3 +23,24 @@ npm install; npm run prettier -- --write "specification/<service>/**/*.json"
  ```
  Then please commit and push changes made by prettier.
  +
  +## Model Validation
  +
  +Run Model Validation locally:
  +```
  +npm install -g oav
  +oav validate-example <swagger-spec-path>
  +```
  +Please see [readme](https://github.com/Azure/oav/blob/master/README.md) for how to install or run tool in details.
  +Or you can run it in [OpenAPI Hub](https://portal.azure-devex-tools.com/tools/static-validation/static/errors/default)
  +Refer to [Semantic and Model Violations Reference](https://github.com/Azure/azure-rest-api-specs/blob/master/documentation/Semantic-and-Model-Violations-Reference.md) for detailed description of validations and how-to-fix guidance.
  +
  +## Semantic Validation
  +Run Semantic Validation locally:
  +```
  +npm install -g oav
  +oav validate-spec <swagger-spec-path>
  +```
  +Please see [readme](https://github.com/Azure/oav/blob/master/README.md) for how to install or run tool in details.
  +Or you can run it in [OpenAPI Hub](https://portal.azure-devex-tools.com/tools/static-validation/static/errors/default)
  +Refer to [Semantic and Model Violations Reference](https://github.com/Azure/azure-rest-api-specs/blob/master/documentation/Semantic-and-Model-Violations-Reference.md) for detailed description of validations and how-to-fix guidance.
  