CCM-11027: Update version check script

Author: chris-elliott-nhsd

.github/workflows/stage-1-commit.yaml

@@ -227,7 +227,7 @@ jobs:
             echo "changed=true" >> $GITHUB_OUTPUT
           fi
 
-          if content=$(git show main:packages/event-schemas/package.json 2>/dev/null); then
+          if content=$(git show origin/main:packages/event-schemas/package.json 2>/dev/null); then
             version=$(jq -r .version <<< $content);
           else
             version=null;