Fixed small bug in RST list parsing.

See #3432.  Previously the parser didn't handle properly this
case:

    * - a
      - b
    * - c
      - d

src/Text/Pandoc/Readers/RST.hs

@@ -548,8 +548,7 @@ listItem :: PandocMonad m
 listItem start = try $ do
   (markerLength, first) <- rawListItem start
   rest <- many (listContinuation markerLength)
-  blanks <- choice [ try (many blankline <* lookAhead start),
-                     many1 blankline ]  -- whole list must end with blank.
+  skipMany1 blankline <|> () <$ lookAhead start
   -- parsing with ListItemState forces markers at beginning of lines to
   -- count as list item markers, even if not separated by blank space.
   -- see definition of "endline"
@@ -557,7 +556,7 @@ listItem start = try $ do
   let oldContext = stateParserContext state
   setState $ state {stateParserContext = ListItemState}
   -- parse the extracted block, which may itself contain block elements
-  parsed <- parseFromString parseBlocks $ concat (first:rest) ++ blanks
+  parsed <- parseFromString parseBlocks $ concat (first:rest) ++ "\n"
   updateState (\st -> st {stateParserContext = oldContext})
   return $ case B.toList parsed of
                 [Para xs] -> B.singleton $ Plain xs

test/command/3432a.md

@@ -0,0 +1,19 @@
+```
+% pandoc -f rst
+* - a
+  - b
+* - c
+  - d
+^D
+<ul>
+<li><ul>
+<li>a</li>
+<li>b</li>
+</ul></li>
+<li><ul>
+<li>c</li>
+<li>d</li>
+</ul></li>
+</ul>
+```
+