Deprecate EventDispatch class #974

Job	Run time
mypy	25s
ruff	6s
sdist	1m 42s
tox (windows-latest)	2m 7s
tox (ubuntu-latest)	3m 46s
test-docs	1m 40s
build (windows-latest, 3.8, x64)	3m 23s
build (windows-latest, 3.8, x86)	4m 2s
build (windows-latest, pypy-3.8, x64)	4m 45s
build (ubuntu-latest, pypy-3.8, x64)	4m 10s
build (ubuntu-latest, 3.8, x64)	3m 16s
parse_sdl (windows-latest, 2.0.14)	39s
build (windows-latest, pypy-3.8, x86)	4m 42s
parse_sdl (macos-latest, 2.30.0)	21s
parse_sdl (macos-latest, 2.0.14)	25s
build-macos (cp38-*_universal2)	5m 37s
parse_sdl (windows-latest, 2.0.16)	42s
parse_sdl (macos-latest, 2.0.16)	23s
parse_sdl (windows-latest, 2.30.0)	54s
linux-wheels (x86_64, cp38-manylinux*)	1m 51s
linux-wheels (x86_64, pp38-manylinux*)	2m 1s
build-macos (pp38-*)	3m 48s
linux-wheels (aarch64, pp38-manylinux*)	11m 15s
linux-wheels (aarch64, cp38-manylinux*)	13m 12s
publish	0s
	1h 15m 12s

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