Validate the value for using namespace during semantic checks to prevent declaring invalid namespaces

[daxian-dbw]

PR Summary

Fixes #17113
Validate the value for using namespace during semantic checks to prevent declaring invalid namespaces.

This PR is to supersede #19134. Thanks @MartinGC94 and @iSazonov for the initial investigation of the regular expression used to validate the namespace values!

I think the right place for doing the check should be in SemanticChecks, so that the AST generated from using statement is unchanged, so there is no need to make changes to tab completion code.

Parsing error thrown at the semantic check stage

AST is unchanged from the parsing

About @JamesWTruher's concern expressed in #19134 (comment), the relevant code is as follows.
The variable typeName is of the type TypeName, so typeName.Name must be a valid type name. Therefore, as long as ns, the namespace value, is valid, the newTypeNameToSearch should be valid. By preventing the declaration of any invalid namespace names, we can guarantee new TypeName(...) won't throw here, so I think we don't need to make any changes here.

PowerShell/src/System.Management.Automation/engine/parser/TypeResolver.cs

Lines 396 to 399 in 4f02a89

	var newTypeNameToSearch = ns + "." + typeName.Name;
	newTypeNameToSearch = typeResolutionState.GetAlternateTypeName(newTypeNameToSearch) ??
	newTypeNameToSearch;
	var newTypeName = new TypeName(typeName.Extent, newTypeNameToSearch);

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[iSazonov]

LGTM.

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Total files changed: 3

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.resx : +3 -0
.ps1 : +4 -0

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