bump zsh-abbr from 7caa26b to fdc486f (#811)

Bumps [custom/plugins/zsh-abbr](https://github.com/olets/zsh-abbr) from `7caa26b` to `fdc486f`.
- [Commits](olets/zsh-abbr@7caa26b...fdc486f)

---
updated-dependencies:
- dependency-name: custom/plugins/zsh-abbr
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>