misc/cgo/testsanitizers: deadlock in TestTSAN/tsan11

[bcmills]

https://build.golang.org/log/6cd850061b3c63c3393144d832c7e47ac50bd8b5

##### ../misc/cgo/testsanitizers
--- FAIL: TestTSAN (13.27s)
    --- FAIL: TestTSAN/tsan11 (256.31s)
        tsan_test.go:53: /tmp/workdir-host-linux-amd64-wsl/tmp/TestTSAN4253803927/tsan11 exited with exit status 2
            SIGQUIT: quit
            PC=0x512ea3 m=0 sigcode=0

Looks like another unbuffered channel passed to signal.Notify (as in #52998).

[gopherbot]

Change https://go.dev/cl/409094 mentions this issue: misc/cgo/testsanitizers: buffer the signal channel in TestTSAN/tsan11

[bcmills]

@gopherbot, please backport to Go 1.18 and 1.17. This is a test-only fix for a spurious deadlock.

[gopherbot]

Backport issue(s) opened: #53114 (for 1.17), #53115 (for 1.18).

Remember to create the cherry-pick CL(s) as soon as the patch is submitted to master, according to https://go.dev/wiki/MinorReleases.

[gopherbot]

Change https://go.dev/cl/408823 mentions this issue: [release-branch.go1.18] misc/cgo/testsanitizers: buffer the signal channel in TestTSAN/tsan11

[gopherbot]

Change https://go.dev/cl/408824 mentions this issue: [release-branch.go1.17] misc/cgo/testsanitizers: buffer the signal channel in TestTSAN/tsan11