Description

The purpose of this task is to remove the xl size in EuiTabs.

It's been discussed in #8128. Two reasons for this request are:

1. Subjectively, it is an atypical font size for tabs (see below). The guidelines say to only use for page titles only, but I don't believe this is a justifiable recommendation.
2. Objectively, we don't use it in Kibana. Search for usage with this regex <EuiTabs[ \w=\{\}>\(\)\n;".-:]* size="xl".

Acceptance criteria

• xl size is removed from EuiTabs