Docs: fix the grammar mistakes in README.md

[najathi]

Description

I have fixed grammar mistakes in the README.md of Bootstrap, ensuring that the text is more readable and clear. The changes include corrections in sentence structure, punctuation, and spelling.

Motivation & Context

These changes are necessary to improve the documentation's readability and professionalism. Clear and correct grammar helps users better understand the content and purpose of the framework, which enhances the overall user experience.

Type of changes

• [x] Documentation (fix or update to documentation)