Add basic typing to pylint/message

[DanielNoord]

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Type of Changes

	Type
✓	🔨 Refactoring

Description

Ref #2079 (comment)
This allows ticking of pylint/message/message_definition.py, pylint/message/message_definition_store.py and pylint/message/message_id_store.py from the list.

[coveralls]

Pull Request Test Coverage Report for Build 1298365659

• 12 of 13 (92.31%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.005%) to 93.11%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pylint/message/message_id_store.py	7	8	87.5%

Totals
Change from base Build 1294541154:	-0.005%
Covered Lines:	13393
Relevant Lines:	14384

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💛 - Coveralls

[Pierre-Sassoulas]

👍