Delete unused `has` fn (was renamed -> `can_haz`)
Delete unused `has` fn (was renamed -> `can_haz`)

In [a previous commit](https://github.com/unixorn/zsh-quickstart-kit/commit/3494ddcde5db247a9913a993616935c784002b1b), the `has` function in `.zshrc` was renamed to `can_haz` but the original `has` function definition was left in the file, despite no longer being used. This commit delete the orphan `has` function definition.
unixorn/zsh-quickstart-kit