fix(waybar): fix cava creating multiple instances

[momcilovicluka]

Pull Request

Description

WaybarCava was creating a new instance of cava every time it was executed. This happens when waybar is restarted/wallpaper is changed

Fixed by killing cava process referencing the same config

Fix: #131

Type of change

Please put an x in the boxes that apply:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update (non-breaking change; modified files are limited to the documentations)
• Technical debt (a code change that does not fix a bug or add a feature but makes something clearer for devs)
• Other (provide details below)

Checklist

Please put an x in the boxes that apply:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My commit message follows the commit guidelines.
• My change requires a change to the documentation.
• I want to add something in Hyprland-Dots wiki.
• I have added tests to cover my changes.
• I have tested my code locally and it works as expected.
• All new and existing tests passed.

Screenshots

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Additional context

Add any other context about the problem here.