Man writer: don't run together successive definitions...

in a tight definition list with multiple definitions
after a term. Closes #11547.

src/Text/Pandoc/Writers/Man.hs

@@ -241,7 +241,7 @@ definitionListItemToMan opts (label, defs) = do
   labelText <- inlineListToMan opts label
   contents <- if null defs
                  then return empty
-                 else liftM vcat $ forM defs $ \case
+                 else case mconcat defs of
                           (x:xs) -> do
                             first' <- blockToMan opts $
                                       case x of

test/writer.man

@@ -359,27 +359,40 @@ Multiple definitions, tight:
 .TP
 apple
 red fruit
+.RS
 computer
+.RE
 .TP
 orange
 orange fruit
+.RS
 bank
+.RE
 .PP
 Multiple definitions, loose:
 .TP
 apple
 red fruit
+.RS
+.PP
 computer
+.RE
 .TP
 orange
 orange fruit
+.RS
+.PP
 bank
+.RE
 .PP
 Blank line after term, indented marker, alternate markers:
 .TP
 apple
 red fruit
+.RS
+.PP
 computer
+.RE
 .TP
 orange
 orange fruit