Remove quotes in data example

Yuri Sulyma · Yuri Sulyma · commit 790d5db3ef5a · 2022-05-01T17:15:03.000-04:00
diff --git a/input/tex/extensions/html.rst b/input/tex/extensions/html.rst
@@ -51,7 +51,7 @@ For example:
 
     (x+1)^2 = \cssId{step1}{\style{visibility:hidden}{(x+1)(x+1)}}
 
-    x = \data{during="quadratic"}{\frac{-b\pm\sqrt{b^2-4ac}}{2a}}
+    x = \data{during=quadratic}{\frac{-b\pm\sqrt{b^2-4ac}}{2a}}
 
 .. Note::
 
