[4.0] Add information to the error message

[chmst]

Summary of Changes

Blog Sample Data can be installed only once. When the user repeats the installation, the installation fails with a message.
For new users this message is somehow cryptic. We can add a clearer information.

Testing Instructions

Install the Blog Sample Data once, then install again and see the error message.

Actual result BEFORE applying this Pull Request

Step 1 Failed with message: Another Tag has the same alias (remember it may be a trashed item).

Expected result AFTER applying this Pull Request

Documentation Changes Required

[chmst]

Thanks!

[ChristineWk]

Got this message. See second sentence:

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[ChristineWk]

I have tested this item ✅ successfully on f1cf9ba

OK, I saw the change now on Github View.

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[rjharishabh]

I have tested this item ✅ successfully on f1cf9ba

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[rjharishabh]

RTC

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[khu5h1]

I have tested this item ✅ successfully on f1cf9ba

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[bembelimen]

I think the communication is good thing in general, but I think this is only a band aid for the deeper problem (and does not fix it at all), which means, if the plugin is changed and e.g. there is a new order of steps or forever reasons the user cleans up the content from step 1, the installation will fail again with another error message.
So I think this should be considerated, too.

[brianteeman]

I agree. If it can only be installed once then it should be removed automatically once it has run

[chmst]

I know that #22634, #20479
It was an attempt to make it a little bit clearer as long as we have not good solution

[pritam825]

I have tested this item ✅ successfully on f1cf9ba

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[wilsonge]

The key thing is you can do only do once on a per-language basis (see #23633 (comment)). I'm merging this for now and if we can find a better solution we can always revert this.

[wilsonge]

Thanks!