Bump .zprezto from 5ff938d to a79c3b4

Bumps [.zprezto](https://github.com/sorin-ionescu/prezto) from `5ff938d` to `a79c3b4`.
- [Commits](sorin-ionescu/prezto@5ff938d...a79c3b4)

---
updated-dependencies:
- dependency-name: ".zprezto"
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>