Underline inline link in CSRF confirmation Panel

This violation was highlighted first by automatic WCAG tests.

Example of violation report

Validation in the test method [dataIsPreservedAfterLogin]
Check for [org.xwiki.test.ui.po.ResubmissionPage] at http://xwikiweb:8080/xwiki/bin/view/NestedLoginIT/dataIsPreservedAfterLogin/?resubmit=%2Fxwiki%2Fbin%2Fsave%2FNestedLoginIT%2FdataIsPreservedAfterLogin%2FWebHome%3Fsrid%3DzH3ZvQ9V&xback=%2Fxwiki%2Fbin%2Fview%2FNestedLoginIT%2FdataIsPreservedAfterLogin%2F&xpage=resubmit.
Found [1] items

1: Links must be distinguishable without relying on color
Description: Ensure links are distinguished from surrounding text in a way that does not rely on color
Help URL: https://dequeuniversity.com/rules/axe/4.8/link-in-text-block?application=axeAPI
Help: Links must be distinguishable without relying on color
Impact: serious
Tags: cat.color, wcag2a, wcag141, TTv5, TT13.a, EN-301-549, EN-9.1.4.1

HTML element:
<a href="http://jira.xwiki.org/">XWiki JIRA</a>
Selector: [a[href$="jira.xwiki.org/"]]
Fix any of the following:
The link has insufficient color contrast of 2.4:1 with the surrounding text. (Minimum contrast is 3:1, link text: #2f70a7, surrounding text: #333333)
The link has no styling (such as underline) to distinguish it from the surrounding text