renovate: make sure cilium-cli test image versions are updated

Migrated from the renovate config in cilium/cilium-cli.

Signed-off-by: Tobias Klauser <tobias@cilium.io>

.github/renovate.json5

@@ -775,6 +775,15 @@
       "matchStrings": [
         "# renovate: datasource=(?<datasource>.*?)\\s+.+_REPO:=(?<depName>.*?)\\s+.+_VERSION:=(?<currentValue>.*)\\s+.+_DIGEST:=(?<currentDigest>sha256:[a-f0-9]+)"
       ]
+    },
+    {
+      "fileMatch": [
+        "^cilium-cli/defaults/defaults\\.go$"
+      ],
+      "matchStrings": [
+        "\/\/ renovate: datasource=(?<datasource>.*?)\\s+.+Image = \"(?<depName>.*):(?<currentValue>.*)@(?<currentDigest>sha256:[a-f0-9]+)\"",
+        "\/\/ renovate: datasource=(?<datasource>.*?) depName=(?<depName>.*?)\\s+Version = \"(?<currentValue>.*)\""
+      ]
     }
   ]
 }