Revert "Bump actions to node 20 (#3461)" (#3462)

This reverts commit defeb8e52b.

As per https://github.com/actions/upload-artifact/issues/478 the new version of upload-artifact includes a breaking change.

.github/workflows/build_esp32_c3.yml

@@ -13,7 +13,7 @@ jobs:
   build-esp32-c3:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
       - name: Build base
         id: base
         uses: ./.github/actions/setup-base
@@ -54,7 +54,7 @@ jobs:
         id: version
 
       - name: Store binaries as an artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v3
         with:
           name: firmware-${{ inputs.board }}-${{ steps.version.outputs.version }}.zip
           path: |