fix: set helm test values

Signed-off-by: Moritz Johner <beller.moritz@googlemail.com>

.github/ci/ct.yaml

@@ -1,6 +1,5 @@
 chart-dirs:
   - deploy/charts
 helm-extra-args: "--timeout=5m"
-helm-extra-set-args: "--set image.tag=main --set webhook.image.tag=main --set certController.image.tag=main"
 check-version-increment: false
 target-branch: main

deploy/charts/external-secrets/ci/main-values.yaml

@@ -1,2 +1,10 @@
 image:
   tag: main
+
+webhook:
+  image:
+    tag: main
+
+certController:
+  image:
+    tag: main