Paste feature does not work if JIRA instance URL configured in Administration contains a slash at the end

Isn't `https://jira.xwiki.org/` a misconfiguration? Vincent Massol 

The Jira macro does not seem to function if I configure such an instance.

Teodor Caras Thx for checking. Two remarks about this:
1) The jira macro works for me when I use https://jira.xwiki.org/. It's just the paste plugin that doesn't work.
2) Even if it didn't work, we need to make it work for usability reasons, since users could very well add the trailing slash. All we need to do is remove the trailing slash in the code.

For 1), I've used:

And:

{{jira id="xwikiorg"}}
XWIKI-2484
XE-291
XWIKI-3677
{{/jira}}

I get:

Not sure what we're doing differently.