Create .git/info dir if it doesn't exist

[hmarr]

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Most of the time, a fresh repository init / clone includes a .git/info directory. However, if a custom git template directory is used, and that template doesn't include an info directory, the .git/info directory will be missing from the new repository checkout. That causes the sparse checkout download strategy to fail when it tries to write to .git/info/sparse-checkout (Homebrew/homebrew-cask-fonts#6961). This change ensures the directory exists before writing that file.

I was able to reproduce the crash in Homebrew/homebrew-cask-fonts#6961 by installing the font, deleting the .git/info directory, then reinstalling the font. After applying this change, I was unable to reproduce the crash.

Fixes Homebrew/homebrew-cask-fonts#6961.

[MikeMcQuaid]

Makes sense, thanks again @hmarr!