cmd/link: TestScript/script_test_basics failures

[gopherbot]

#!watchflakes
default <- pkg == "cmd/link" && test == "TestScript/script_test_basics"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestScript/script_test_basics
=== PAUSE TestScript/script_test_basics
=== CONT  TestScript/script_test_basics
    run.go:223: 2025-10-21T01:20:34Z
    run.go:225: $WORK=/home/swarming/.swarming/w/ir/x/t/TestScriptscript_test_basics581250037/001
    run.go:232: 
        BOTO_CONFIG=/home/swarming/.swarming/w/ir/x/a/gsutil-bbagent/.boto
        CIPD_ARCHITECTURE=arm64
        CIPD_CACHE_DIR=/home/swarming/.swarming/w/ir/cache/cipd_cache
        CIPD_PROTOCOL=v2
...
        WORK=/home/swarming/.swarming/w/ir/x/t/TestScriptscript_test_basics581250037/001
        TMPDIR=/home/swarming/.swarming/w/ir/x/t/TestScriptscript_test_basics581250037/001/tmp
        
        # Test of the linker's script test harness. (7.400s)
        > go build
        > [!cgo] skip
        [condition not met]
        > cc -c testdata/mumble.c
    run.go:232: FAIL: testdata/script/script_test_basics.txt:6: cc -c testdata/mumble.c: exec: WaitDelay expired before I/O complete
--- FAIL: TestScript/script_test_basics (7.41s)

— watchflakes