Update async-tungstenite requirement from 0.28 to 0.29 #613

Job	Run time
clippy	35s
msrv (1.63)	1m 2s
test (ubuntu-latest, nightly)	53s
test (ubuntu-latest, beta)	58s
test (ubuntu-latest, stable)	54s
test (windows-latest, nightly)	2m 25s
test (windows-latest, beta)	2m 15s
test (windows-latest, stable)	2m 42s
test (macos-latest, nightly)	57s
test (macos-latest, beta)	44s
test (macos-latest, stable)	1m 1s
fmt / fmt	7s
security_audit / security_audit	2m 42s
	17m 15s

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