C#: Improve cs/invalid-string-formatting and add to the Code Quality suite.

[michaelnebel]

In this PR we

• Add the cs/invalid-string-formatting to the code quality suite.
• Re-write tests to use inline expectations tests; In this process a couple of faulty testcases were discovered and these were corrected (for instance - we only check that format strings are valid in case there are insertions).

Improve the cs/invalid-string-formatting query by

• Adding invalid string format results for string.Format where no additional arguments are provided (for instance string.Format("{")). Also start taking CompositeFormat versions of Format methods into account and consider System.Text.CompositeFormat.Parse a method that parses format strings and might throw exceptions and cause a runtime crash.
• Add support for more format methods like generic versions of string.Format and StringBuilder.AppendFormat and also add support for MemoryExtensions.TryWrite.
• Remove false positives related to Console.WriteLine(string) and friends (methods that itsn't format methods).
• Remove false positives related to `Console.WriteLine(string, ReadOnlySpan) (methods that use params collection type overloads).

  Review commit by commit is encouraged.

  @hvitved : The data flow configurations are quite similar. Is it a better approach to use flow state to track calls to CompositeFormat.Parse? (instead of merging two similar graphs).

[michaelnebel]

DCA

• There doesn't appear to be any changes to performance or results for our DCA suite.
• The level produced on our DCA suite for this query looks acceptable (query is not unreasonable noisy).