fix: package.json & package-lock.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-SOCKETIO-1024859

.github/workflows/docker.yml

@@ -1,34 +0,0 @@
-name: Docker
-
-on: ["push", "pull_request"]
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v1
-      - name: Cache Docker layers
-        uses: actions/cache@v2
-        with:
-          path: /tmp/.buildx-cache
-          key: ${{ runner.os }}-buildx-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-buildx-
-      - name: Build
-        uses: docker/build-push-action@v2
-        with:
-          context: ./
-          file: ./Dockerfile
-          builder: ${{ steps.buildx.outputs.name }}
-          push: false
-          cache-from: type=local,src=/tmp/.buildx-cache
-          cache-to: type=local,dest=/tmp/.buildx-cache-new
-      - name: Move cache
-        run: |
-          rm -rf /tmp/.buildx-cache
-          mv /tmp/.buildx-cache-new /tmp/.buildx-cache
-      - name: Image digest
-        run: echo ${{ steps.docker_build.outputs.digest }}

Dockerfile

@@ -1,18 +0,0 @@
-FROM node:14
-
-# Create app directory
-WORKDIR /usr/src/app
-
-# Install app dependencies
-# A wildcard is used to ensure both package.json AND package-lock.json are copied
-# where available (npm@5+)
-COPY package*.json ./
-
-RUN npm install
-# If you are building your code for production
-# RUN npm ci --only=production
-
-# Bundle app source
-COPY . .
-
-CMD [ "sh", "-c", "node server.js" ]

package.json

@@ -4,7 +4,7 @@
   "description": "my first socket.io app",
   "dependencies": {
     "color-convert": "^1.9.3",
-    "express": "^4.20.0",
+    "express": "^4.17.1",
-    "socket.io": "^3.0.0"
+    "socket.io": "^2.4.0"
   }
 }