Update deploy.yml

Update actions/cache to v4 to fix deploy failures on github.
Should fix deploy error on [PR#1286](#1286)

Author: thomas-zimmerman

.github/workflows/deploy.yml

@@ -24,7 +24,7 @@ jobs:
 
       - name: Cache
         id: cache
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ./node_modules
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}