Add more automatic variables to PSAvoidAssignmentToAutomaticVariables that are not read-only but should still not be assigned to in most cases

[bergmeister]

PR Summary

Closes #712
Closes #1183

The list of variables was extracted from #712 and it i s the union of non-readonly automatic variables in Windows PowerShell and PowerShell Core. Some of those variables can be assigned to in very special cases but the point of this rule is to rather warn that assignment to automatic variables happens and if the author knows what he/she/they are doing then they can/should suppress the rule

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.

[rjmholt]

I feel we should avoid embedding clausal descriptions in variable names if we can -- and also I can't think of an automatic variable that's not problematic to assign to (since, being automatic, they could be reassigned unexpectedly)

Suggested change

	private static readonly IList<string> _automaticVariablesThatCouldBeProblematicToAssignTo = new List<string>()
	private static readonly IList<string> _automaticVariables = new List<string>()

[bergmeister]

I wanted to differentiate from the _readOnlyAutomaticVariables variable above where PowerShell actually itself throws an error when trying to assign, those variables don't.

[rjmholt]

Well one is readonly variables and the other is just automatic variables, no? So _readonlyVariables and _automaticVariables or _writeableAutomaticVariables maybe?

[rjmholt]

I'd just prefer not to call the variable something that embeds a sentence

[bergmeister]

How about _writeableAutomaticVariables and _readonlyAutomaticVariables?

[rjmholt]

👌