DBText::Summary only adds ellipsis to the first sentence

[michalkleiner]

Affected Version

4.8 latest

Description

Looking at the code at https://github.com/silverstripe/silverstripe-framework/blob/4/src/ORM/FieldType/DBText.php#L120, it seems the $add is only added to the first sentence if it's longer than $maxWords.
It's not used after line https://github.com/silverstripe/silverstripe-framework/blob/4/src/ORM/FieldType/DBText.php#L144 to append to the second or other sentences.

Steps to Reproduce

Provide a text with two or more sentences and set maxWords to fall in the middle of the second sentence.

[michalkleiner]

Found this issue when working on tests for #9696. Once that's merged in, a test case for this issue can be added to the providerSummary provider there.