net/http: TestTimeoutHandlerContextCanceled failures

[gopherbot]

#!watchflakes
post <- pkg == "net/http" && test == "TestTimeoutHandlerContextCanceled"

Issue created automatically to collect these failures.

Example (log):

--- FAIL: TestTimeoutHandlerContextCanceled (0.00s)
    --- FAIL: TestTimeoutHandlerContextCanceled/h2 (0.47s)
        serve_test.go:2542: got unexpected Write in handler: <nil>, want &{%!g(string=context canceled)}

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
post <- pkg == "net/http" && test == "TestTimeoutHandlerContextCanceled"

2023-05-24 16:46 freebsd-riscv64-unmatched go@42f387aa net/http.TestTimeoutHandlerContextCanceled (log)

--- FAIL: TestTimeoutHandlerContextCanceled (0.00s)
    --- FAIL: TestTimeoutHandlerContextCanceled/h2 (0.47s)
        serve_test.go:2542: got unexpected Write in handler: <nil>, want &{%!g(string=context canceled)}

— watchflakes