make sure checks out correct branch

Author: gigapod

.github/workflows/ports_sparkfun.yml

@@ -3,8 +3,7 @@ name: sparkfun ports
 on:
   release:
     types: [created]
-
-  workflow_dispatch:
+    
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -20,6 +19,8 @@ jobs:
     - uses: actions/checkout@v4
       with:
         path: 'micropython repo'
+        ref: 'release/${{ github.event.release.tag_name }}'
+        
     - name: Install RP2 package
       run: source tools/ci.sh && ci_rp2_setup
     # - name: Install mimxrt package # Currently redundant since it does the same arm setup as rp2, but in future if these diverge, uncomment this...