[CI] Use dev branch for test

Signed-off-by: Frederic Pillon <frederic.pillon@st.com>

Author: fpistm

.github/workflows/Continuous-Integration.yml

@@ -53,6 +53,8 @@ jobs:
     - name: Compilation
       id: Compile
       uses: stm32duino/actions/compile-examples@master
+      with:
+        additional-url: 'https://github.com/stm32duino/BoardManagerFiles/raw/dev/STM32/package_stm_index.json'
 
     # Use the output from the `Compile` step
     - name: Compilation Errors