PartDesign: Double tooltip text when hovering over new sketch button

### Problem description

### Workbench affected?

Core (App, Gui,...)

### Steps to reproduce

See https://github.com/FreeCAD/FreeCAD/issues/29587#issuecomment-4315635782

### Expected behavior

Tooltip that doesn't show 'New Sketch' twice

### Actual behavior

Tooltip that shows 'New Sketch' twice (as shown in screenshot above)

### Development version About Info (in Safe Mode)

```shell
OS: Windows 10 build 19045
Architecture: x86_64
Version: 1.2.0dev.20260421 (Git shallow)
Build date: 2026/04/21 23:21:45
Build type: Release
Branch: (HEAD detached at 449725202)
Hash: 449725202d0ab581516aacad59d62cdce80db82a
Python 3.11.15, Qt 6.8.3, Coin 4.0.8, Vtk 9.3.1, boost 1_86, Eigen3 3.4.0, PySide 6.8.3
shiboken 6.8.3, xerces-c 3.3.0, IfcOpenShell 0.8.2, OCC 7.8.1
Locale: Turkish/Türkiye (tr_TR) [ OS: Turkish/Türkiye (tr_TR) ]
Stylesheet/Theme/QtStyle: FreeCAD.qss/FreeCAD Dark/
Navigation Style/Orbit Style/Rotation Mode: Blender/Rounded Arcball/Window center
Logical DPI/Physical DPI/Pixel Ratio: 96/127.628/1
Installed mods:
* Curved Shapes 1.0.14
* Curves workbench 0.6.71
* FreeCAD_SketchArch
```

### Last known good version (optional)

```shell

```