Update CI setup and enable Dependabot

.github/dependabot.yml

@@ -0,0 +1,7 @@
+# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "weekly"

.github/workflows/ci.yml

@@ -1,3 +1,4 @@
+# Adapted from https://code.visualstudio.com/api/working-with-extensions/continuous-integration#github-actions
 name: Tests and publishing
 on:
   push:
@@ -20,13 +21,13 @@ jobs:
           - macos-latest
           - windows-latest
         node:
-          - 16.x
+          - 18.x
     runs-on: ${{ matrix.os }}
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - name: Install Node.js
-      uses: actions/setup-node@v3
+      uses: actions/setup-node@v4
       with:
         node-version: ${{ matrix.node }}
     - name: Compile
@@ -45,7 +46,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - name: Create package
       run: |
         npm install
@@ -57,6 +58,6 @@ jobs:
       env:
         VSCE_PAT: ${{ secrets.VSCE_PAT }}
     - name: Upload package to release
-      uses: softprops/action-gh-release@v1
+      uses: softprops/action-gh-release@v2
       with:
         files: '*.vsix'