Add missing TestNamespace to ScaledJob validation test template (#5989)

This scaledjob test template was missing its namespace, which doesn't
generally matter for the test -- the test is just checking if the
webhook works, it doesn't care where the scaledjob ends up.

Where it does matter, is if you happen to run this test suite in a more
restrictive environment where you can't write to the default namespace,
because you fail with a namespace-related creation error instead of the
expected "no triggers defined in the ScaledObject/ScaledJob" error.

This just adds the namespace to the template so it's just like all the
other ones in the test suite.

Signed-off-by: John Kyros <jkyros@redhat.com>

tests/internals/scaled_job_validation/scaled_job_validation_test.go

@@ -32,6 +32,7 @@ apiVersion: keda.sh/v1alpha1
 kind: ScaledJob
 metadata:
   name: {{.EmptyTriggersSjName}}
+  namespace: {{.TestNamespace}}
 spec:
   jobTargetRef:
     template: