ci: Group k8s mod updates for dependabot (#316)

Author: jimmidyson

.github/dependabot.yml

@@ -12,11 +12,21 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
+    groups:
+      k8s:
+        patterns:
+          - "k8s.io*"
+          - "sigs.k8s.io*"
 
   - package-ecosystem: "gomod"
     directory: "/common"
     schedule:
       interval: "weekly"
+    groups:
+      k8s:
+        patterns:
+          - "k8s.io*"
+          - "sigs.k8s.io*"
 
   - package-ecosystem: "gomod"
     directory: "/hack/third-party/capa"