Sender details styling updates

[nimishavijay]

Steps to reproduce

1. Open Mail
2. Click on a message
3. Click on the sender email address in the header of a message to open the full sender/recipient details

Expected behavior

Recipients should look exactly like NcUserBubbles

Actual behavior

Looks similar to NcUserBubble but is bigger and not pill-shaped

Mail app version

No response

Nextcloud version

No response

Mailserver or service

No response

Operating system

No response

PHP engine version

None

Nextcloud memory caching

No response

Web server

None

Database

None

Additional info

follow-up to #12966 (comment)
cc @sturlan