Add vitest to GitHub actions (#9162)

* Add vitest to GHA

* Make a clean install

* switching from jsx to React.createElement()

* Update and rename test.yml to vitest.yml

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Co-authored-by: Steve Persch <steve.persch@pantheon.io>
Co-authored-by: Steve Persch <stevector@users.noreply.github.com>

.github/workflows/vitest.yml

@@ -0,0 +1,23 @@
+name: JavaScript Unit Tests
+on:
+  pull_request:
+    paths:
+      - 'src/**'
+      - '.github/workflows/vitest.yml'
+    types:
+      - opened
+      - synchronize
+      - reopened
+      - ready_for_review
+  workflow_dispatch:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 'latest'
+      - run: npm ci
+      - run: npx vitest src/components

src/components/omniSidebarNav/helpers.js

@@ -17,10 +17,12 @@ const turnItemsIntoLinks = (item, activePage) => {
   // If the link is external, add an icon to indicate that.
   // Internal links will start with a slash.
   if (item.link.startsWith('http')) {
-    linkText = (
-      <>
-        <Icon iconName="externalLink" /> {item.title}
-      </>
+    linkText = React.createElement(
+      React.Fragment,
+      null,
+      React.createElement(Icon, { iconName: "externalLink" }),
+      " ",
+      item.title
     );
   }