Fix typo in image alt text and update CTA wording

Author: iammajid

content/success-stories/walbusch.en.html

@@ -11,7 +11,7 @@
 # Hero Section
 hero_description: "Following the termination of Boxcryptor, Walbusch is now relying on Cryptomator Hub to manage sensitive data securely and transparently using AES-256 encryption."
 hero_image: "/img/success-stories/walbusch.png"
-hero_image_alt: "Wahlbusch company building"
+hero_image_alt: "Walbusch company building"
 hero_image_company_logo: "/img/success-stories/walbusch-logo.svg"
 
 # Quote Section

i18n/en.yaml

@@ -17,7 +17,7 @@
 - id: success_story_cta_get_started
   translation: "Get Started"
 - id: success_story_cta_book_demo
-  translation: "Book Demo"
+  translation: "Book a Demo"
 - id: nav_cta
   translation: "Get Started"
 - id: nav_products
@@ -1138,7 +1138,7 @@
 - id: book_demo_message_placeholder
   translation: "Tell us more about your specific needs or questions..."
 - id: book_demo_submit
-  translation: "Book Demo"
+  translation: "Book a Demo"
 - id: book_demo_success_title
   translation: "Demo Request Received!"
 - id: book_demo_success_message