Make use of prism in periodic tests not cross compile. (#27054)

Co-authored-by: lostluck <13907733+lostluck@users.noreply.github.com>
diff --git a/sdks/go/pkg/beam/transforms/periodic/periodic.go b/sdks/go/pkg/beam/transforms/periodic/periodic.go
index f8752dc..5a7b4d0 100644
--- a/sdks/go/pkg/beam/transforms/periodic/periodic.go
+++ b/sdks/go/pkg/beam/transforms/periodic/periodic.go
@@ -100,7 +100,7 @@
 	for currentOutputTimestamp.Before(currentTime) {
 		if rt.TryClaim(currentOutputIndex) {
 			emit(mtime.FromTime(currentOutputTimestamp), currentOutputIndex)
-			currentOutputIndex += 1
+			currentOutputIndex++
 			currentOutputTimestamp = mtime.Time(sd.Start).ToTime().Add(sd.Interval * time.Duration(currentOutputIndex))
 			currentTime = time.Now()
 			we.UpdateWatermark(currentOutputTimestamp)
diff --git a/sdks/go/pkg/beam/transforms/periodic/periodic_test.go b/sdks/go/pkg/beam/transforms/periodic/periodic_test.go
index 7553e1f..a34edf8 100644
--- a/sdks/go/pkg/beam/transforms/periodic/periodic_test.go
+++ b/sdks/go/pkg/beam/transforms/periodic/periodic_test.go
@@ -21,12 +21,16 @@
 	"time"
 
 	"github.com/apache/beam/sdks/v2/go/pkg/beam"
+	"github.com/apache/beam/sdks/v2/go/pkg/beam/options/jobopts"
 	_ "github.com/apache/beam/sdks/v2/go/pkg/beam/runners/prism"
 	"github.com/apache/beam/sdks/v2/go/pkg/beam/testing/passert"
 	"github.com/apache/beam/sdks/v2/go/pkg/beam/testing/ptest"
 )
 
 func TestMain(m *testing.M) {
+	// Since we force loopback with prism, avoid cross-compilation.
+	f, _ := os.CreateTemp("", "dummy")
+	*jobopts.WorkerBinary = f.Name()
 	os.Exit(ptest.MainRetWithDefault(m, "prism"))
 }