fix bug lwm2m Content Format M14

[nickAS21]

Pull Request description

Problem:
When ContentFormat="lwm2m+tlv " is in the request and the client does not support it, then the lechan Client M14/M4 library code throws an error:

before:
{"result":"NOT_ACCEPTABLE"}

After:
application/src/test/java/org/thingsboard/server/transport/lwm2m/rpc/sql/RpcLwm2mIntegrationWriteCborTest.java
{"result":"CHANGED"}

General checklist

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• Labels that classify your pull request have been added.
• The milestone is specified and corresponds to fix version.
• Description references specific issue.
• Description contains human-readable scope of changes.
• Description contains brief notes about what needs to be added to the documentation.
• No merge conflicts, commented blocks of code, code formatting issues.
• Changes are backward compatible or upgrade script is provided.
• Similar PR is opened for PE version to simplify merge. Crosslinks between PRs added. Required for internal contributors only.

Back-End feature checklist

• Added corresponding unit and/or integration test(s). Provide written explanation in the PR description if you have failed to add tests.
• If new dependency was added: the dependency tree is checked for conflicts.
• If new service was added: the service is marked with corresponding @TbCoreComponent, @TbRuleEngineComponent, @TbTransportComponent, etc.
• If new REST API was added: the RestClient.java was updated, issue for Python REST client is created.
• If new yml property was added: make sure a description is added (above or near the property).

[ViacheslavKlimov]

Why did you leave commented code?