allow string for badge attribute of l:task

[mawinter69]

The documentation can be interpreted that the badge attribute accepts a String as argument. But in reality it requires an instance of jenkins.management.Badge

The effect can be seen on the Design Library
https://weekly.ci.jenkins.io/design-library/Layouts/twoColumn
Where a String is passed but is not shown.

This change allows either a Badge object or something else which is then just printed.

Testing done

I tested this by modifying the sidepanel of the ComputerSet page
<l:task href="${h.getNearestAncestorUrl(request,it)}/" icon="symbol-computer"
title="${%Nodes}" badge="${it._all.size()}"/>
The page then properly show me the number of agents (without having a tooltip)
On the plugins page the number of updates is still shown with a tooltip.

Before:

After:

Proposed changelog entries

• Allow string for badge attribute of <l:task ...>.

Proposed upgrade guidelines

N/A

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[daniel-beck]

What's the use case for this? AFAIUI, badges in #7084 started as int but became Badge when #6995 was merged in in 70966cf, docs might just not have been adapted.

[mawinter69]

OK so far it seems nobody uses the badge attribute except for the pluginmanager. So maybe updating the docs might be enough and we should fix the design library

[daniel-beck]

CC @janfaracik who wrote jenkinsci/design-library-plugin#90.

[mawinter69]

Close in favor of #8469