bump zsh-abbr from c95e7d4 to 447708a (#861)

Bumps [custom/plugins/zsh-abbr](https://github.com/olets/zsh-abbr) from `c95e7d4` to `447708a`.
- [Release notes](https://github.com/olets/zsh-abbr/releases)
- [Commits](olets/zsh-abbr@c95e7d4...447708a)

---
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>