Modify Pages "How to" and "Styles"

[dipinknair]

Description of the modifications

• Remove redundant tabs ⏭️ Modify documentation #399

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• Create one style tab for all styles
• Fix abstraction page formatting
  • Add cards
  • Fix code snippets width

Useful links and references

https://dev.docs.pyansys.com/how-to/index.html
https://dev.docs.pyansys.com/abstractions/app-interface.html