[5.0] Joomla content plugin: Check if param is set before comparing

[Hackwar]

Summary of Changes

When adding a menu item to edit/creates articles, this code checks if the parameter enable_category is equal to 1 and if the catid is set. However, when you add this code not via the menu manager, but manually via some script, it will throw a notice when that parameter is not set. This PR adds a simple check if that param is present before comparing it. Since not setting this equals to 0, this should be fine.

Testing Instructions

Right now, before #41489 is merged, the testing sampledata can not be run, because that parameter is missing. So, install Joomla and run the testing sampledata.

Actual result BEFORE applying this Pull Request

Adding the testing sampledata fails with a notice in the AJAX call.

Expected result AFTER applying this Pull Request

Now it works.

Link to documentations

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

• No documentation changes for manual.joomla.org needed

[Quy]

I have tested this item ✅ successfully on 807c364

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/41500.}

[HLeithner]

thanks

[HLeithner]

thanks