CI: Don't include debug .elf files in artifacts.

.github/workflows/micropython-picow.yml

@@ -134,7 +134,6 @@ jobs:
       working-directory: micropython/ports/rp2/build-${{matrix.board}}
       run: |
         cp firmware.uf2 $RELEASE_FILE.uf2
-        cp firmware.elf $RELEASE_FILE.elf
 
     - name: Store .uf2 as artifact
       uses: actions/upload-artifact@v3
@@ -142,12 +141,6 @@ jobs:
         name: ${{env.RELEASE_FILE}}.uf2
         path: micropython/ports/rp2/build-${{matrix.board}}/${{env.RELEASE_FILE}}.uf2
 
-    - name: Store .elf as artifact
-      uses: actions/upload-artifact@v3
-      with:
-        name: ${{env.RELEASE_FILE}}.elf
-        path: micropython/ports/rp2/build-${{matrix.board}}/${{env.RELEASE_FILE}}.elf
-
     - name: Upload .uf2
       if: github.event_name == 'release'
       uses: actions/upload-release-asset@v1