Muse writer: don't wrap displayMath into <verse>

<verse> is a block tag and displayMath is an inline element.
Writing <verse> around displayMath could result in nested
<verse> tags.

src/Text/Pandoc/Writers/Muse.hs

@@ -363,11 +363,8 @@ inlineToMuse (Quoted DoubleQuote lst) = do
 inlineToMuse (Cite _  lst) = inlineListToMuse lst
 inlineToMuse (Code _ str) = return $
   "<code>" <> text (substitute "</code>" "<</code><code>/code>" str) <> "</code>"
-inlineToMuse (Math InlineMath str) =
-  lift (texMathToInlines InlineMath str) >>= inlineListToMuse
-inlineToMuse (Math DisplayMath str) = do
-  contents <- lift (texMathToInlines DisplayMath str) >>= inlineListToMuse
-  return $ "<verse>" <> contents <> "</verse>" <> blankline
+inlineToMuse (Math t str) =
+  lift (texMathToInlines t str) >>= inlineListToMuse
 inlineToMuse (RawInline (Format f) str) =
   return $ "<literal style=\"" <> text f <> "\">" <> text str <> "</literal>"
 inlineToMuse LineBreak = return $ "<br>" <> cr

test/Tests/Writers/Muse.hs

@@ -330,7 +330,7 @@ tests = [ testGroup "block elements"
             ]
           , testGroup "math"
             [ "inline math" =: math "2^3" =?> "2<sup>3</sup>"
-            , "display math" =: displayMath "2^3" =?> "<verse>2<sup>3</sup></verse>"
+            , "display math" =: displayMath "2^3" =?> "2<sup>3</sup>"
             , "multiple letters in inline math" =: math "abc" =?> "<em>abc</em>"
             ]
           , "raw inline"

test/writer.muse

@@ -520,7 +520,7 @@ Ellipses…and…and….
  - 223
  - <em>p</em>-Tree
  - Here’s some display math:
-   <verse><verbatim>$$\frac{d}{dx}f(x)=\lim_{h\to 0}\frac{f(x+h)-f(x)}{h}$$</verbatim></verse>
+   <verbatim>$$\frac{d}{dx}f(x)=\lim_{h\to 0}\frac{f(x+h)-f(x)}{h}$$</verbatim>
  - Here’s one that has a line break in it:
    <em>α</em> + <em>ω</em> × <em>x</em><sup>2</sup>.