Respect $ZDOTDIR in uninstaller

[mcornella]

Describe the bug

Uninstaller does not respect the actual install directory (#10537) and it won't respect the .zshrc location if installed on a different directory using $ZDOTDIR.

Steps to reproduce

1. Create ZDOTDIR directory if not yet created: mkdir -p ~/.config/zsh
2. Install OMZ in custom ZDOTDIR: ZDOTDIR=~/.config/zsh sh install.sh
3. Run uninstall_oh_my_zsh
4. .zshrc and $ZSH folder are not removed

Expected behavior

• Correct OMZ folder is removed
• .zshrc file is looked for in $ZDOTDIR

Screenshots and recordings

$ uninstall_oh_my_zsh 
Are you sure you want to remove Oh My Zsh? [y/N] y
Removing ~/.oh-my-zsh
Looking for original zsh config...
No original zsh config found
Thanks for trying out Oh My Zsh. It's been uninstalled.
Don't forget to restart your terminal!

OS / Linux distribution

Any

Zsh version

Any

Oh My Zsh version

master (b2313ec)

Terminal emulator

Any

If using WSL on Windows, which version of WSL

None

Additional context

No response