fix: upgrade redis from 3.0.2 to 3.1.0

Snyk has created this PR to upgrade redis from 3.0.2 to 3.1.0.

See this package in npm:
https://www.npmjs.com/package/redis

See this project in Snyk:
https://app.snyk.io/org/klemek/project/81af650f-8c8e-4116-b289-95415c85d8a7?utm_source=github&utm_medium=upgrade-pr

.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 }}

package.json

@@ -14,9 +14,9 @@
     "ncp": "^2.0.0",
     "node-prismjs": "^0.1.0",
     "prismjs": "^1.23.0",
-    "redis": "^3.0.2",
+    "redis": "^3.1.0",
     "rss": "^1.2.2",
-    "showdown": "^2.0.2"
+    "showdown": "^1.9.1"
   },
   "devDependencies": {
     "coveralls": "^3.0.4",