docs: update `usage/channels` #4653

Job	Run time
mypy	1m 6s
pyright	42s
slotscheck	23s
validate	21s
Test Minimal Application with Base Dependencies	17s
Test server integration (uvicorn<0.27.0)	38s
Test Minimal Pydantic 1 application	20s
Test server integration (uvicorn>=0.27.0)	41s
test-platform-compat	0s
test (3.10) / test	1m 47s
test (3.11) / test	1m 38s
test (3.12) / test	3m 9s
test (3.13) / test	2m 5s
test (3.8) / test	2m 42s
test (3.9) / test	1m 52s
build-docs	2m 13s
codeql	1m 55s
upload-test-coverage	14s
sonar	55s
	22m 58s

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