chore: remove unneeded constant

Author: metacosm

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/config/ControllerConfiguration.java

@@ -5,9 +5,6 @@
 import java.util.Set;
 
 public interface ControllerConfiguration<R extends CustomResource> {
-
-  String WATCH_ALL_NAMESPACES_MARKER = "ALL_NAMESPACES";
-
   String getName();
 
   String getCRDName();