Updated About Section Text for Better Relevance

[akshay0611]

PR Description:
This PR improves the "About Us" section by replacing generic placeholder text with a more relevant and engaging description that better represents the gym’s mission, training programs, and supportive environment.

Changes:

• Rewrote the section text to focus on the gym’s offerings and motivation.
• Highlighted various training programs and the importance of community support.
• Ensured a clear and engaging tone for better readability.

Screenshot:

Fixes: #13