SpinBox update_on_text_changed = true regression: Can't input decimals.

[dknoma]

Tested versions

• Reproducible in: v4.3.stable, v4.4.dev6 [1f47e4c]
• Not reproducible in: v4.2.stable

System information

Godot v4.3.stable.mono - Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1080 (NVIDIA; 32.0.15.6603) - Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz (8 Threads)

Issue description

Setting Update on Text Changed to true prevents decimals from being input. It seems to be similar to what happened with #81989. You can copy and paste decimal numbers into the SpinBox just fine, but trying to type a decimal will do nothing. Changing step to a decimal value < 1 still doesn't allow a decimal to be typed. This is true for both GDscript and C# in 4.3 & 4.4-dev6, but not in 4.2 (as #81989 fixed it in that version)

Steps to reproduce

1. Create a new scene
2. Add a SpinBox node
3. Set Update on Text Changed to true
4. Run the current scene
5. Type decimal (.) into the SpinBox

Minimal reproduction project (MRP)

N/A