chore: Update index.md (#3911)

Making a few small typo changes.

# Description

## Problem\*

Resolves <!-- Link to GitHub Issue -->

## Summary\*



## Additional Context



## Documentation\*

Check one:
- [ ] No documentation needed.
- [ ] Documentation included in this PR.
- [ ] **[Exceptional Case]** Documentation to be submitted in a separate
PR.

# PR Checklist\*

- [ ] I have tested the changes locally.
- [ ] I have formatted the changes with [Prettier](https://prettier.io/)
and/or `cargo fmt` on default settings.

docs/docs/getting_started/installation/index.md

@@ -41,5 +41,5 @@ noirup
 Done. That's it. You should have the latest version working. You can check with `nargo --version`.
 
 You can also install nightlies, specific versions
-or branches, check out the [noirup repository](https://github.com/noir-lang/noirup) for more
+or branches. Check out the [noirup repository](https://github.com/noir-lang/noirup) for more
 information.