Update Clickr Theme to v2.10, 2 issues fixed in this release

Version 2.10 of the Clikr Theme is out.

Fixed bugs:

CONF-17610/[CLKR-36|https://studio.plugins.atlassian.com/browse/CLKR-36] - User full name is an XSS vector in the Clickr theme
CLKR-35 - Comment gets doubly HTML encoded when deployed by maven-confluence-plugin