Update Documentation for Message Object Instantiation

[ojasvajain]

Overview

This PR updates the documentation to add guidance around how and when to instantiate a Message object.

Checklist

• Contains customer facing changes? Including API/behavior changes
• Did you add sufficient unit test and/or integration test coverage for this PR?

References

#2128

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[pranavrth]

I would recommend something like this.

Suggested change

	" Instantiate a Message object. This is primarily intended for "
	"testing and mock scenarios (e.g. unit tests). All parameters are optional.\n"
	" Instantiate a Message object.\n"
	"\n"
	" .. warning::"
	" This constructor is intended **only for testing and mock scenarios**."
	" Do **not** use user instantiated Message object in mainstream APIs or in production."
	" Using this constructor outside of test environments may result in"
	" unexpected behavior, security issues, or inconsistent application state.\n"
	"\n"
	" All parameters are optional.\n"

[ojasvajain]

Makes sense. Have incorporated the change.

[pranavrth]

LGTM!. Just a nit.

[pranavrth]

Check failing build and rebase the PR.

[MSeal]

Build failure looks to be unrelated to the change and the kafka resource failed when it should have given a 400 response. Try rerunning as I believe it will pass on second try here. If we see it reocurring we'll need to fix in master branch.

[sonarqube-confluent]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarQube

[ojasvajain]

Build failure looks to be unrelated to the change and the kafka resource failed when it should have given a 400 response. Try rerunning as I believe it will pass on second try here. If we see it reocurring we'll need to fix in master branch.

Yes, it passed after re-running

[pranavrth]

LGTM!.