[typescript] use Collections.addAll() rather than loop

Created by: cal101

Collection related refactorings:

• replaces for/foreach loops to use Collections.addAll() where possible,
• replaces for/foreach loops to use Collection.addAll() where possible,
• replaces for/foreach loops to use Collection.removeAll() where possible.

AddAllRatherThanLoopCleanUp from AutoRefactor applied by erefactor. For AutoRefactor see https://github.com/JnRouvignac/AutoRefactor .

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