fix(typing): Fix typing in websocket listener class #4331

Job	Run time
slotscheck	45s
pyright	1m 7s
mypy	1m 26s
Test server integration (uvicorn<0.27.0)	59s
Test Minimal Application with Base Dependencies	37s
Test server integration (uvicorn>=0.27.0)	58s
Test Minimal Pydantic 1 application	48s
test-platform-compat	0s
validate	17s
test (3.10) / test	2m 6s
test (3.11) / test	1m 56s
test (3.12) / test	3m 29s
test (3.8) / test	3m 17s
test (3.9) / test	2m 9s
build-docs	3m 22s
codeql	1m 55s
upload-test-coverage	16s
sonar	0s
	25m 27s

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