Update PyInstaller example and docs for loading tilesets #941

Job	Run time
mypy	18s
ruff	5s
sdist	38s
tox (ubuntu-latest)	1m 25s
tox (windows-latest)	1m 33s
parse_sdl (windows-latest, 2.0.14)	45s
parse_sdl (windows-latest, 2.0.16)	46s
test-docs	1m 18s
parse_sdl (macos-latest, 2.0.14)	27s
linux-wheels (x86_64, cp38-manylinux*)	1m 54s
parse_sdl (macos-latest, 2.0.16)	23s
build (ubuntu-latest, 3.8, x64)	2m 42s
linux-wheels (x86_64, pp38-manylinux*)	1m 52s
build (ubuntu-latest, pypy-3.8, x64)	2m 24s
linux-wheels (aarch64, cp38-manylinux*)	10m 40s
build-macos (cp38-*_universal2)	5m 32s
build (windows-latest, 3.8, x64)	3m 28s
linux-wheels (aarch64, pp38-manylinux*)	9m 36s
build-macos (pp38-*)	4m 21s
build (windows-latest, pypy-3.8, x64)	5m 6s
build (windows-latest, 3.8, x86)	4m 15s
build (windows-latest, pypy-3.8, x86)	4m 24s
publish	0s
	1h 3m 52s

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