windows/svc/mgr: rename service in TestMyService

TestMyService uses the same service name as service in
golang.org/x/sys/windows/svc.TestExample.

https://build.golang.org sometimes schedules TestMyService and
TestExample to run at the same time. If that happens, tests fail,
because they were not designed to run in parallel.

This CL renames service in TestMyService, so it does not clash with
TestExample.

Fixes golang/go#42211

Change-Id: I928c2ebbae77de3540f5ce16948fb96eeeed836d
Reviewed-on: https://go-review.googlesource.com/c/sys/+/267604
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

windows/svc/mgr/mgr_test.go

@@ -7,6 +7,7 @@
 package mgr_test
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"sort"
@@ -217,7 +218,7 @@ func TestMyService(t *testing.T) {
 		t.Skip("skipping test in short mode - it modifies system services")
 	}
 
-	const name = "myservice"
+	const name = "mymgrservice"
 
 	m, err := mgr.Connect()
 	if err != nil {
@@ -285,9 +286,9 @@ func TestMyService(t *testing.T) {
 	}
 
 	testSetRecoveryActions(t, s)
-	testRebootMessage(t, s, "myservice failed")
+	testRebootMessage(t, s, fmt.Sprintf("%s failed", name))
 	testRebootMessage(t, s, "") // delete reboot message
-	testRecoveryCommand(t, s, "sc query myservice")
+	testRecoveryCommand(t, s, fmt.Sprintf("sc query %s", name))
 	testRecoveryCommand(t, s, "") // delete recovery command
 
 	remove(t, s)