Missing spacing to border in welcome help bubbles

Missing spacing to border in welcome help bubbles: the title of the bubble can touch the border which looks a little bit odd...

Describe your environment

• OS: Fedora 37
• Jami version: 202302052213
• What build you are using: jami.net

Steps to reproduce

• Open Jami

Additional information

assigned to @sblin

added good first issue sprintto review ui/ux labels

mentioned in commit 5e106ea6

Ce sera fixé avec la prochaine version

closed

removed sprintto review label