feat: update action runtime to node 20 (#2340)

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: 16.x
+          node-version: 20.x
           cache: npm
       - run: npm ci
       - run: npm run build

__test__/integration-tests.sh

@@ -8,7 +8,7 @@ if [[ "$(docker images -q $IMAGE 2> /dev/null)" == "" || $ARG1 == "build" ]]; th
     echo "Building Docker image $IMAGE ..."
 
     cat > Dockerfile << EOF
-FROM node:16-alpine
+FROM node:20-alpine
 RUN apk --no-cache add git git-daemon
 RUN npm install jest jest-environment-jsdom --global
 WORKDIR /cpr

action.yml

@@ -85,7 +85,7 @@ outputs:
   pull-request-head-sha:
     description: 'The commit SHA of the pull request branch.'
 runs:
-  using: 'node16'
+  using: 'node20'
   main: 'dist/index.js'
 branding:
   icon: 'git-pull-request'