Better visual separation between avatars of commit author and pipeline triggerer in pipeline list

Problem

Currently 2 avatars are shown in the pipeline list:

• commit author avatar
• pipeline triggerer avatar

This creates confusion and a little bit of a mess as they are very near each other and alike.

Proposal

Better positioning of the trigger avatar and/or making them different in sizes.

Design

• Separate triggerer column
• make avatar if triggerer bigger