docs: fix `INSTALL.md` link

[Saeden]

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [x] I have read the CONTRIBUTING document.
• [ ] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.

This is an extremely minor fix but the link to the INSTALL.md in the README file was incorrect. I ofcourse could just edit the link everytime but seeing as the change is so small I thought I would make a PR to fix it :)

[utkuozdemir]

Ah, that's a mistake I introduced recently, thank you very much!