cmd/cgo/internal/testcarchive: remove 1-minute timeout

The 1-minute test timeout seems a bit arbitrary. Use
internal/testenv.Command, which applies t.Deadline to subcommand.

For #67566.

Change-Id: If84c96e353bdfaf02c9b123758198e031305ae32
Reviewed-on: https://go-review.googlesource.com/c/go/+/599056
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

Author: cherrymui

src/cmd/cgo/internal/testcarchive/carchive_test.go

@@ -1224,22 +1224,14 @@ func TestManyCalls(t *testing.T) {
 	}
 
 	argv := cmdToRun("./testp7")
-	cmd = exec.Command(argv[0], argv[1:]...)
+	cmd = testenv.Command(t, argv[0], argv[1:]...)
 	sb := new(strings.Builder)
 	cmd.Stdout = sb
 	cmd.Stderr = sb
 	if err := cmd.Start(); err != nil {
 		t.Fatal(err)
 	}
 
-	timer := time.AfterFunc(time.Minute,
-		func() {
-			t.Error("test program timed out")
-			cmd.Process.Kill()
-		},
-	)
-	defer timer.Stop()
-
 	err = cmd.Wait()
 	t.Logf("%v\n%s", cmd.Args, sb)
 	if err != nil {
@@ -1284,22 +1276,14 @@ func TestPreemption(t *testing.T) {
 	}
 
 	argv := cmdToRun("./testp8")
-	cmd = exec.Command(argv[0], argv[1:]...)
+	cmd = testenv.Command(t, argv[0], argv[1:]...)
 	sb := new(strings.Builder)
 	cmd.Stdout = sb
 	cmd.Stderr = sb
 	if err := cmd.Start(); err != nil {
 		t.Fatal(err)
 	}
 
-	timer := time.AfterFunc(time.Minute,
-		func() {
-			t.Error("test program timed out")
-			cmd.Process.Kill()
-		},
-	)
-	defer timer.Stop()
-
 	err = cmd.Wait()
 	t.Logf("%v\n%s", cmd.Args, sb)
 	if err != nil {