Merge pull request #24 from linuxserver/v1-mods-3rd-party

Accept `pull_request_target` and check out PR ref

.github/workflows/docker-mod-builder.yml

@@ -18,12 +18,29 @@ on:
       MOD_VERSION:
         required: false
         type: string
+    secrets:
+      CR_USER:
+        required: false
+      CR_PAT:
+        required: false
+      DOCKERUSER:
+        required: false
+      DOCKERPASS:
+        required: false
 
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - name: Check Out Repo (Commit)
+        uses: actions/checkout@v3
+        if: ${{ github.event_name != 'pull_request_target' }}
+
+      - name: Check Out Repo (PR)
+        uses: actions/checkout@v3
+        if: ${{ github.event_name == 'pull_request_target' }}
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
 
       - name: Dump payload
         env: