[clang-tools-extra] [clang-tools-extra] Fix typos in Modularize.rst (PR #99256)

[David Spickett via cfe-commits]

DavidSpickett wrote:

I saw your email in the merge box so I've gone ahead and landed it (I think the workflow that checks for a private email may only be re-run when the changes in the PR are updated).

https://github.com/llvm/llvm-project/pull/99256