fix ci add-path

Author: hathach

.github/workflows/githubci.yml

@@ -31,7 +31,7 @@ jobs:
         # 9.3.1-1.2.1 is xpack modified version which significantly increased compiled size to 6-7KB and cause flash overflow.
         # Skip this version for now, we will try again with next official release from ARM
         xpm install --global @xpack-dev-tools/[email protected]
-        echo "::add-path::`echo $HOME/opt/xPacks/@xpack-dev-tools/arm-none-eabi-gcc/*/.content/bin`"
+        echo `echo $HOME/opt/xPacks/@xpack-dev-tools/arm-none-eabi-gcc/*/.content/bin` >> $GITHUB_PATH
     
     - name: Build
       run: python3 tools/build_all.py