use test config

Author: diegomarquezp

google-cloud-spanner/src/test/resources/META-INF/native-image/com.google.cloud/google-cloud-spanner/native-image.properties

@@ -1 +1,3 @@
-Args=--initialize-at-build-time=org.junit.runner.RunWith,java.lang.annotation.Annotation
+Args=--initialize-at-build-time=org.junit.runner.RunWith,java.lang.annotation.Annotation \
+ --initialize-at-build-time=org.junit.experimental.categories.Category \
+ --initialize-at-build-time=org.junit.runners.model.FrameworkField