fix: support non-literal types in template literal strings

[flugg]

When given a template literal type which contains a number type, for instance:

type Foo = `${number}`;

The generator fails with Unknown type "number".

This PR solves this by simply returning a StringType when a template literal string contains a number type, which makes sense, because JSON Schema can't really represent these types easily. I feel like making a regex-converter for these types is a bit overkill.

[domoritz]

Thank you for the pull request.

[flugg]

This change seemed to affect how template literal strings worked in mapped types and broke another test. I changed it to check for LiteralType, UnionType and AliasType, which is what the extractLiterals function checks below. Looks like this solved everything and allows for other non-literal types than just numbers.

[domoritz]

Thank you!

[github-actions]

🚀 PR was released in v1.2.0 🚀