cmd/go: TestScript/test_fuzz_deadline failures

```
#!watchflakes
default <- pkg == "cmd/go" && test == "TestScript/test_fuzz_deadline"
```

Issue created automatically to collect these failures.

Example ([log](https://ci.chromium.org/b/8721382945696968225)):

=== RUN TestScript/test_fuzz_deadline
=== PAUSE TestScript/test_fuzz_deadline
=== CONT TestScript/test_fuzz_deadline
script_test.go:139: 2025-03-03T22:00:03Z
script_test.go:141: $WORK=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-3784789766/tmpdir2367466655/test_fuzz_deadline1330060082
2025/03/03 22:00:03 serving /git/hello/info/refs?service=git-upload-pack
2025/03/03 22:00:03 serving /git/hello/git-upload-pack
script_test.go:163:
PATH=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-3784789766/tmpdir2367466655/testbin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/cache/tools/bin:/home/swarming/.swarming/w/ir/bbagent_utility_packages:/home/swarming/.swarming/w/ir/bbagent_utility_packages/bin:/home/swarming/.swarming/w/ir/cipd_bin_packages:/home/swarming/.swarming/w/ir/cipd_bin_packages/bin:/home/swarming/.swarming/w/ir/cache/cipd_client:/home/swarming/.swarming/w/ir/cache/cipd_client/bin:/home/swarming/.swarming/cipd_cache/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOME=/no-home
...
--- FAIL: FuzzDeadline (0.00s)
--- FAIL: FuzzDeadline/seed#0 (0.00s)
fuzz_deadline_test.go:14: function got true; want false
FAIL
exit status 1
FAIL fuzz 0.020s
[exit status 1]
> go test -run=FuzzDeadline -timeout=1s -wantdeadline=true
[stdout]
PASS
...
fuzz: elapsed: 0s, gathering baseline coverage: 0/1 completed
fuzz: elapsed: 0s, gathering baseline coverage: 1/1 completed, now fuzzing with 2 workers
fuzz: elapsed: 1s, execs: 32394 (29372/sec), new interesting: 0 (total: 1)
--- FAIL: FuzzDeadline (1.10s)
context deadline exceeded
FAIL
exit status 1
FAIL fuzz 1.109s
script_test.go:163: FAIL: testdata/script/test_fuzz_deadline.txt:22: go test -fuzz=FuzzDeadline -timeout=0 -fuzztime=1s -wantdeadline=false: exit status 1
--- FAIL: TestScript/test_fuzz_deadline (80.28s)

— [watchflakes](https://go.dev/wiki/Watchflakes)

Start with cmd/go's TestScript/test_fuzz_deadline and the script at testdata/script/test_fuzz_deadline.txt, then inspect the failing fuzz_deadline_test.go output in the linked log. Reproduce the failure and determine why the deadline expectations differ; done means the test passes reliably without changing its intended deadline behavior.

Written by the indexing model from the issue text.