[ci] Use emsdk-setup github action

See https://github.com/emscripten-core/setup-emsdk

Author: sbc100

.github/workflows/ci.yml

@@ -357,12 +357,9 @@ jobs:
     - name: install ninja
       run: sudo apt-get install ninja-build
     - name: emsdk install
-      run: |
-        mkdir $HOME/emsdk
-        git clone --depth 1 https://github.com/emscripten-core/emsdk.git $HOME/emsdk
-        $HOME/emsdk/emsdk update-tags
-        $HOME/emsdk/emsdk install tot
-        $HOME/emsdk/emsdk activate tot
+      uses: emscripten-core/setup-emsdk@v15
+      with:
+        version: tot
     - name: override emscripten repository
       if: ${{ env.EMSCRIPTEN_REPO != '' }}
       run: |