@Xref needs to be on one line

git-svn-id: https://svn.r-project.org/R/trunk@89641 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: ripley

doc/manual/R-exts.texi

@@ -17690,8 +17690,8 @@ functions that should be used instead:
 @item PRVALUE SET_PRVALUE
 @itemx PRCODE SET_PRCODE R_PromiseExpr
 @itemx PRENV SET_PRENV
-       Use the binding access API added in @R{} 4.6.0. @xref{Working
-       with variable bindings}.
+       Use the binding access API added in @R{} 4.6.0.
+       @xref{Working with variable bindings}.
 @end table
 
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