[4.0] Fix markup in dashboard

[Quy]

Summary of Changes

In the dashboard, the link to add a new item is inside a link. This PR fixes invalid markup.

Testing Instructions

Go to Content Dashboard
View page source

Actual result

[ChristineWk]

I have tested this item ✅ successfully on 6dd2255

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/27061.}

[infograf768]

I have tested this item ✅ successfully on 6dd2255

---

_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/27061.}

[infograf768]

rtc

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/27061.}

[infograf768]

tks