Add support for async generator injections #1279

Job	Run time
Run tests with different pydantic versions	3m 12s
Run tests (3.12)	1m 49s
Run tests with coverage	2m 49s
Run tests (3.11)	1m 57s
Run tests (3.10)	1m 54s
Run tests (3.8)	1m 53s
Run linters (mypy)	1m 41s
Run tests (3.9)	1m 51s
Run tests (3.13)	1m 59s
Run linters (pylint)	1m 35s
Run linters (pydocstyle)	1m 30s
Run linters (flake8)	1m 34s
	23m 44s

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