fix: use fixed source for command-chain scripts

Author: frenchwr

snap/snapcraft.yaml

@@ -262,15 +262,15 @@ parts:
     plugin: dump
     source-type: git
     source: https://github.com/canonical/openvino-toolkit-snap.git
-    source-branch: openvino-toolkit-2404
+    source-tag: 2024.5.0-0
     stage:
       - command-chain/openvino-launch
 
   command-chain-openvino-ai-plugins-gimp:
     plugin: dump
     source-type: git
     source: https://github.com/canonical/openvino-ai-plugins-gimp-snap.git
-    source-branch: main
+    source-commit: 7d20266d73ba25cd49aae55f0a2157911fb6bc75  # TODO: update to tagged release once upstream branch merged
     stage:
       - command-chain/openvino-ai-plugins-gimp-launch