CI: Bump Node version to latest LTS (#305)

Co-authored-by: Peter Murphy <[email protected]>

Author: pete-murphy

.github/workflows/tests.yml

@@ -23,7 +23,7 @@ jobs:
       - name: Set up Node toolchain
         uses: actions/setup-node@v1
         with:
-          node-version: "12.x"
+          node-version: "18.x"
 
       - name: Cache NPM dependencies
         uses: actions/cache@v2