move pow wasm lib out to a separate repo

.github/workflows/coverage.yml

@@ -61,7 +61,7 @@ jobs:
 
       - uses: actions/setup-node@v2
         with:
-          node-version: '14.x'
+          node-version: '16.x'
 
       - name: start smtp server
         run: docker run -d -p 1080:1080 -p 10025:1025  maildev/maildev --incoming-user admin --incoming-pass password
@@ -73,9 +73,6 @@ jobs:
           profile: minimal
           override: true
 
-      - name: Install wasm-pack
-        run: curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh
-
       - name: Build frontend
         run: make frontend