chore: improve type hints

[waketzheng]

1. Remove 3 type:ignore comments
2. Apply X|Y style which reduces import lines

[coveralls]

Pull Request Test Coverage Report for Build 11976639446

Details

• 20 of 22 (90.91%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.03%) to 89.509%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tortoise/init.py	20	22	90.91%
<!--	Total:	20	22	90.91%	-->

Totals
Change from base Build 11963373385:	-0.03%
Covered Lines:	6232
Relevant Lines:	6854

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💛 - Coveralls