Fix issue 617 (support EnumMember on enums within types for query string param objects)

[todthomson]

What kind of change does this PR introduce?

Bug fix.

What is the current behavior?

See: #617.

What is the new behavior?

Query string paramter types that have enum properties will respect [EnumMember(Value = "foo")].

i.e. Not just "direct parameter enums", but where your types have enum properties (see 617 for the example code).

What might this PR break?

I don't think it will break anything, as I have:

• Included appropriate passing tests.
• Checked that it doesn't break any existing tests.
• Should not break existing code (unless in the slim chance that they have types with enums for query string parameters which already have EnumMember on them, where that is currently achieving nothing, which would be "strange", but sadly not impossible...).

Please check if the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features).
• Docs have been added / updated (for bug fixes / features).

Other information:

None.

[dnfadmin]

All CLA requirements met.

[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.