Temporarily swap boards branch to migrate-4mb-to-esptool

Author: tyeth

.github/workflows/build-clang-doxy.yml

@@ -82,6 +82,7 @@ jobs:
         with:
           repository: adafruit/Wippersnapper_Boards
           path: ws-boards
+          ref: migrate-4mb-to-esptool
       - name: Install CI-Arduino
         run: bash ci/actions_install.sh
       - name: Install extra Arduino libraries