DEVX-8869: Add Verify2 Template and Template Fragmetn snippets

[superchilled]

This PR adds code snippets for Verify v2 custom templates. Specifically it adds the following files:

Templates

• list-templates.rb
• get-template.rb
• create-template.rb
• update-template.rb
• delete-template.rb

Template Fragments

• list-template-fragments.rb
• get-template-fragment.rb
• create-template-fragment.rb
• update-template-fragment.rb
• delete-template-fragment.rb

The PR also updates the .env-example file with the appropriate environment variables to support the new code snippets.