Move pytest-mypy-plugins tests into mypy jobs #1613

Job	Run time
Check types using pyright	13s
Verify dev env	9s
Build & verify package	16s
Tests on pypy-3.10	22s
Run doctests & render changelog	17s
Tests & Mypy on 3.13	1m 2s
Tests & Mypy on 3.12	1m 8s
Tests & Mypy on 3.14	1m 56s
Tests & Mypy on 3.11	1m 7s
Tests & Mypy on 3.10	53s
Tests & Mypy on 3.9	9s
Combine & check coverage	0s
required-checks-pass	2s
	7m 34s

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