fix: use same wording for button labels to create instances (#174)

The button for GPU instances has a "Create a GPU Instance" label while
the button for confidential VMs reads "Create Confidential".
Harmonized the two.

Author: odesenfans

src/components/pages/console/confidential/ConfidentialDashboardPage/cmp.tsx

@@ -34,7 +34,7 @@ export default function ConfidentialDashboardPage() {
               title="Confidential Instance"
               description="Protect your sensitive workloads with our Confidential VMs. Designed for maximum privacy and security, ensuring your execution and data stays safe."
               buttonUrl="/console/computing/confidential/new"
-              buttonText="Create Confidential"
+              buttonText="Create a Confidential Instance"
               externalLinkText="Developer docs"
               externalLinkUrl={NAVIGATION_URLS.docs.confidentials}
             />