Docs: Corrected command to activate virtual environment on windows.

[dhruvpal05]

Description

Made a minor change to the command to activate virtual environment on windows in INSTALL.md

Changes Made

changed this .\venv\Scripts\activate.bat to this .\venv\Scripts\activate

Checklist

• I have read and followed the contributing guidelines.
• I have tested my changes thoroughly and they work as expected.
• I have added necessary tests for the changes made.
• I have updated the documentation to reflect the changes made.
• My code follows the project's coding style and standards.
• I have added appropriate commit messages and comments for my changes.

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