Use .nvmrc file for setting up Node version in Actions

.github/workflows/cli-test.yml

@@ -62,7 +62,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 

.github/workflows/main.yml

@@ -22,7 +22,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 
@@ -64,7 +64,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 
@@ -110,7 +110,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 
@@ -149,7 +149,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 
@@ -183,7 +183,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 
@@ -251,7 +251,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
           cache: 'npm'
           cache-dependency-path: extensions/ql-vscode/package-lock.json
 

.github/workflows/release.yml

@@ -22,7 +22,7 @@ jobs:
 
       - uses: actions/setup-node@v3
         with:
-          node-version: '18.15.0'
+          node-version-file: extensions/ql-vscode/.nvmrc
 
       - name: Install dependencies
         run: |

docs/node-version.md

@@ -15,14 +15,14 @@ You can find this info by seleting "About Visual Studio Code" from the top menu.
 
 The following files will need to be updated:
 
-- `.github/workflows/cli-test.yml` - the "node-version: '[VERSION]'" setting
-- `.github/workflows/main.yml` - all the "node-version: '[VERSION]'" settings
-- `.github/workflows/release.yml` - the "node-version: '[VERSION]'" setting
-- `extensions/ql-vscode/.nvmrc` - this will enable nvm to automatically switch to the correct node version when you're in the project folder
-- `extensions/ql-vscode/package-lock.json` - the "engines.node: '[VERSION]'" setting
+- `extensions/ql-vscode/.nvmrc` - this will enable nvm to automatically switch to the correct Node
+   version when you're in the project folder. It will also change the Node version the GitHub Actions
+   workflows use.
 - `extensions/ql-vscode/package.json` - the "engines.node: '[VERSION]'" setting
 - `extensions/ql-vscode/package.json` - the "@types/node: '[VERSION]'" dependency
 
+Then run `npm install` to update the `extensions/ql-vscode/package-lock.json` file.
+
 ## Node.js version used in tests
 
 Unit tests will use whatever version of Node.js is installed locally. In CI this will be the version specified in the workflow.