Make Settings type detection more robust

[Tadas]

PR Summary

It was unable to parse settings hashtable, when that hashtable has been wrapped as a PSObject. This started happening in PS 7.2, I was using Import-PowerShellDataFile to read some settings before passing them on to Invoke-ScriptAnalyzer.

There was some code to handle wrapped strings, might as well do that with all parameter types.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Change is not breaking
• Make sure all .cs, .ps1 and .psm1 files have the correct copyright header
• Make sure you've added a new test if existing tests do not effectively test the code changed and/or updated documentation
• This PR is ready to merge and is not Work in Progress.
  • If the PR is work in progress, please add the prefix WIP: to the beginning of the title and remove the prefix when the PR is ready.

[Tadas]

Related to #807 but that particular scenario was being covered.

[bergmeister]

Thanks and sorry for late review. Kicked off CI and pending that all good.

[andyleejordan]

Hopefully the tests still pass because I didn't test that myself!