feat(docs): allow control tags

[Otetz]

Default tags generation are exhaustively. I am add ability to set Tags for endpoint, and other tags don't auto-generated for this endpoint.
Also, if set Tags to empty strings slice, OpenAPI interpret this as default tag.
But if Tags as nil (by default) automatic generation work as previously.

[meteran]

Hi @Otetz, thanks for the contribution. Your change is indeed right, but please add at least one test for it and I will merge it. The test should cover at least 2 endpoints - one with default and one with custom tags.

Please also change the target branch to dev. I will create a proper changelog before merging it to main branch and create a release.

[Otetz]

Done.

[meteran]

Thanks a lot. I'm merging it and going to make a release later today, together with the openapi3 library update.