chore(deps): update helm chart cert-manager to v1.21.2

apps/templates/cert-manager-helm.yaml

@@ -12,7 +12,7 @@ spec:
   project: default
   source:
     repoURL: https://charts.jetstack.io
-    targetRevision: v1.15.5
+    targetRevision: v1.21.2
     chart: cert-manager
     helm:
       parameters:

apps/templates/longhorn-helm.yaml

@@ -16,7 +16,7 @@ spec:
   sources:
     - chart: longhorn
       repoURL: https://charts.longhorn.io/
-      targetRevision: 1.12.1 # Replace with the Longhorn version you'd like to install or upgrade to
+      targetRevision: 1.7.3 # Replace with the Longhorn version you'd like to install or upgrade to
       helm:
         values: |
           persistence: