[Website] update akvelon case study: update text and fix landing page (#35133)

* feat: change text

* fix: add learn more to quotes Akvelon

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Co-authored-by: Bulat Safiullin <v-safiullinb@microsoft.com>

Author: bullet03

website/www/site/data/en/quotes.yaml

@@ -85,6 +85,7 @@
   icon: icons/quote-icon.svg
   logoUrl: /images/logos/powered-by/akvelon.png
   linkUrl: case-studies/akvelon/index.html
+  linkText: Learn more
 - text: With Apache Beam and Dataflow, Credit Karma achieved a 99% uptime for critical data pipelines, a significant jump from 80%. This reliability, coupled with faster development (1 engineer vs. 3 estimated), has been crucial for enabling real-time financial insights for our more than 140 million members.
   icon: icons/quote-icon.svg
   logoUrl: images/logos/powered-by/credit-karma.png