[char.traits.require] Fix excess vertical space in table.

Author: zygoloid

source/strings.tex

@@ -155,7 +155,7 @@
 Copies correctly even where the ranges \tcode{[p,p+n)} and \tcode{[s,s+n)} overlap.\br \returns \tcode{s}.    &   linear  \\ \rowsep
 \tcode{X::copy(s,p,n)}  &   \tcode{X::char_type*}   &
 \expects
-\tcode{p} not in \tcode{[s,s+n)}. \br
+\tcode{p} not in \tcode{[s,s+n)}.\par
 \returns
 \tcode{s}.\br
 for each \tcode{i} in