Describe the bug
Graphic shapes representing input/output parameters overlap each other when adding a new tool into canvas.

To Reproduce
Steps to reproduce the behavior:

1. Open g.gui.modeler
2. Model -> Add command
3. Select some tool, eg. v.buffer
4. Specify input, output and distance parameter
5. Input and output parameters overlap each other

Expected behavior
Shapes representing parameters should not overlap each other.

System description (please complete the following information):

• Operating System: Linux
• GRASS GIS version: main
• 3.9.9 (main, Nov 16 2021, 10:24:31)
• 4.0.7 gtk3 (phoenix) wxWidgets 3.0.5