BUG: Theme reset doesn't actually reset Flow search bar size

### Checks

- [x] I have checked that this issue has not already been reported.

- [x] I am using the latest version of Flow Launcher.

- [ ] I am using the prerelease version of Flow Launcher.

### Problem Description

Reset button below doesn't rest the width/height of Flow. Tested on Win10, Flow 2.1.3 using the Circle theme

### To Reproduce

1. ... Manually change size of search bar (setting for Fixed Window Size needs to be off
2. ... Open Settings - Theme - Edit pen icon and hit Reset
3. ... Activate Flow and search bar size is the same and hasn't reset

Restarting Flow doesn't help

### Screenshots

### Flow Launcher Version

2.1.3

### Windows Build Number

Microsoft Windows [Version 10.0.19045.7663]

### Error Log

Reproduce the issue in Flow Launcher 2.1.3 with the Circle theme: disable Fixed Window Size, change the search bar dimensions, then use Settings - Theme - Edit and press Reset. Trace the theme reset path and the search bar size settings. Done means the reset restores the default width and height and the change remains after restarting Flow.

Written by the indexing model from the issue text.