Update github actions to use Node 20

Author: Joe Pavitt

.github/workflows/deploy-docs.yml

@@ -19,7 +19,7 @@ jobs:
           fetch-depth: 0
       - uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
         with:
-          node-version: 18
+          node-version: 20
           cache: npm
       - run: npm ci
       - name: Build

.github/workflows/publish-private.yml

@@ -13,7 +13,7 @@ jobs:
     uses: 'flowfuse/github-actions-workflows/.github/workflows/build_node_package.yml@v0.42.0'
     with:
       node: '[
-              {"version": "18", "tests": true, "lint": true},
+              {"version": "20", "tests": true, "lint": true},
             ]'
 
   publish:

.github/workflows/publish-release.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
         with:
-          node-version: 18
+          node-version: 20
       - name: Install Dependencies
         run: npm ci
       - name: Run Tests