TextWrapWord will cause crash in RichText

[aynakeya]

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

If a label in a Scroll container have its text starts with a space. and its Wrapping equals TextWrapWord.

eg

l :=widget.NewLabel(" AAAA")
l.Wrapping = fyne.TextWrapWord

Then program will crash at RichText.go with index out of range -1

How to reproduce

Run code in Example code will cause program to crash

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("Hello World")

	texts := make([]fyne.CanvasObject, 32)
	for i := 0; i < len(texts); i++ {
		l := widget.NewLabelWithStyle(
			" AAAA",
			fyne.TextAlignCenter, fyne.TextStyle{})
		l.Wrapping = fyne.TextWrapWord
		texts[i] = l
	}
	vbox := container.NewVBox(texts...)
	scroll := container.NewScroll(vbox)
	w.SetContent(scroll)
	w.Resize(fyne.NewSize(360, 540))
	w.ShowAndRun()
}

Fyne version

v2.2.4

Go compiler version

1.19

Operating system

Windows

Operating system version

Windows 10

Additional Information

No response

[aynakeya]

Maybe its the same problem as #3291

[andydotxyz]

Please can you test against v2.3.0 which was released yesterday. Lots of text code was upgraded.

[aynakeya]

Please can you test against v2.3.0 which was released yesterday. Lots of text code was upgraded.

Problem still exists in v2.3.0

[andydotxyz]

Fixed on develop, thanks @alexballas