Issue templates should be made more relevant to people

LGTM has shutdown and will be gone soon. Issue templates should stop referencing it.

Also, maybe we could have more expressive labels than just question and false positive. Perhaps we could have a general label for actual general issues so that they are not labelled as questions.

https://github.com/github/codeql/issues/11222#tasklist-block-42e4fafd-3330-45b5-b58d-f3f5a3ced1fa