remove spilled newline

Author: ben-schwen

NEWS.md

@@ -359,7 +359,6 @@
 
 7. In rare situations a data.table object may lose its internal attribute that holds a self-reference. New helper function `.selfref.ok()` tests just that. It is only intended for technical use cases. See manual for examples.
 
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 ## data.table [v1.17.8](https://github.com/Rdatatable/data.table/milestone/41) (6 July 2025)
 
 1. Internal functions used to signal errors are now marked as non-returning, silencing a compiler warning about potentially unchecked allocation failure. Thanks to Prof. Brian D. Ripley for the report and @aitap for the fix, [#7070](https://github.com/Rdatatable/data.table/pull/7070).