Add .cache directory to .gitignore

[Zheaoli]

Bug report

Bug description:

For now, there are many people use vscode + clangd to developer cpython. But the clangd will generate a .cache directory under the base directory and the behavior could not be customized. So I think maybe we can add the .cache to the .gitignore

FYI clangd/clangd#946

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-132134: Add to .cache directory .gitignore file #132135
• [3.13] gh-132134: Add the clangd .cache directory to .gitignore (GH-132135) #132144
• [3.12] gh-132134: Add the clangd .cache directory to .gitignore (GH-132135) #132145