Tooltip disappears if mouse moves and TooltipText property has been modified

### Tested versions

- Reproducible in v4.3.dev5.mono.official [89f70e98d]
- Other versions not yet tested

### System information

Windows 11 - Vulkan, Forward+

### Issue description

When mousing over a control and a Tooltip popup appears, it will remain visible so long as the mouse remains hovering over the control that spawned it. This is not true if the control has had its TooltipText property modified since the tooltip was instantiated.

https://github.com/godotengine/godot/assets/22286697/98296521-3b88-44fb-9e45-0d4466050bd2

### Steps to reproduce

1. Create a control node with some TooltipText value
2. Have the TooltipText value be modified after spawning the tooltip
3. Move your mouse (still within the bounds of the control node) and observe that the spawned tooltip will be freed

### Minimal reproduction project (MRP)

[Tooltip MRP.zip](https://github.com/godotengine/godot/files/14968252/Tooltip.MRP.zip)

No source file, test, or entry point is named. Start by running the attached Tooltip MRP on the reported Godot version and trace the Control TooltipText update and spawned tooltip behavior. Done means moving the mouse within the control no longer frees the visible tooltip after TooltipText changes, with a regression test if the relevant test location is identified.

Written by the indexing model from the issue text.