Fix problematic backquote that causes zsh completion not working

[darkyzhou]

Description of the change

My environment:

• MacOS 10.15.6
• zsh 5.7.1 (x86_64-apple-darwin19.0)

In my environment, zsh will complain about a unmatched " error when loading zsh completion file _termius.
The error goes like this: /path/to/_termius:413: unmatched "

After checking the source of _termius, I found it is the problematic backquote that causes the error and after correcting it to a single quote, the problem gets fixed.

I wonder if this is a rare case which only happens in macos + zsh environment like me since I didn't find any issues reporting it :/

Type of change

• Feature
• Codebase Improvements
• Critical security bugs
• Hotfix

Reviewer's checklist

• The code does not have any obvious logic errors.
• All cases specified in the requirements are fully implemented.
• There is sufficient automated testing for the new code. Existing automated tests were rewritten to account for code changes.
• The new code conforms to existing style guidelines.