Inline math can end with newline

[Roope Salmi]

The parsing for inline math properly rejects newlines at the start, i.e.

$
not math$

is not recognized as math.

However, at the end only ASCII spaces are rejected:

commonmark-hs/commonmark-extensions/src/Commonmark/Extensions/Math.hs

Lines 46 to 48 in c6123a1

 else if T.all (==' ') (T.takeEnd 1 contents) 
         -- don't allow math to end with SPACE + $ 
         then mzero 

So this is recognized:

$is math
$

I wouldn't expect there to be a difference going by the phrasing here:

commonmark-hs/commonmark-extensions/test/math.md

Lines 14 to 16 in c6123a1

 In inline math, the opening `$` must not be followed by 
 a whitespace, and the closing `$` must not be 
 preceeded by whitespace.