Duplicate diagnostics for CompilerDirective in incremental

[fm-117]

In some incremental parsing scenarios, diagnostics created during compiler directive processing are duplicated.

ProcessingDiagnostics are created:

• to signal errors that occur during EI-Legacy suffixing
• to signal errors for unsupported altered REPLACE by a REPLACING clause

Technical

• identify in which collection the duplicate is originally found (either in ProcessingDiagnostics itself or after being copied into ParserDiagnostics on CodeElementsLine)
• see also #2335 to think about another model.

To reproduce, remove the exclusion of UseCopyWithReplaceDeclaredWithReplacing / UseCopyWithReplaceDeclaredWithReplacing2 in incremental tests.