fix(docs): Fix docs generation for method return values

[tricki]

The @returns tags were ignored and instead @return was used, but the tag object wasn't properly converted to a string resulting in the output [object Object].

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Unit tests (npm test) were run locally and passed
• E2E Tests (npm run test.karma.prod) were run locally and passed
• Prettier (npm run prettier) was run locally and passed

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

@returns was ignored and @return wasn't serialized, rendering it unusable.

GitHub Issue Number: N/A

What is the new behavior?

@returns is properly output.

Does this introduce a breaking change?

• Yes
• No

Technically, you could say it's a breaking change but from a buggy state so it's very unlikely anyone has used @return before.

Testing

Other information

Before:

After:

[rwaskiewicz]

Thanks @tricki! I took your PR for a spin, and things are looking good. I had one small ask regarding backwards compatibility. Let me know what you think!

[rwaskiewicz]

Note to future me/team/community members. This is technically a breaking change to the output, but is simultaneously a nice bug fix for doc generation. Since the output was previously unusable (it output [Object object]), I am erring on the side of this being added to the next minor release of Stencil