Minor graphic glitch with checkbox

[matwachich]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

A tiny little annoying white line inside CheckBox

How to reproduce

Check widget in a window

Screenshots

Example code

package main

import (
	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/app"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/widget"
)

func main() {
	a := app.New()
	w := a.NewWindow("Test")

	w.SetContent(container.NewHSplit(
		widget.NewLabel("Testing"),
		widget.NewCheck("Test", nil),
	))

	w.Resize(fyne.NewSize(400, 400))
	w.CenterOnScreen()
	w.ShowAndRun()
}

Fyne version

2.3.2

Go compiler version

1.20

Operating system and version

Windows 10

Additional Information

It seems like a rounding issue, because when moving the CheckBox the glitch disapears sometimes

[andydotxyz]

Working on this but sadly will need to be 2.4 - the only way to fix the alignment is to move the check BG to a theme resource, which requires an additional API I think