Bug 1623777 - Replace fancy right single quotation mark with less fan…

…cy one. r=gw,jrmuizel

So that moz-phab stops throwing an encoding error.

Differential Revision: https://phabricator.services.mozilla.com/D67560

gfx/wr/webrender/src/picture.rs

@@ -3937,7 +3937,7 @@ pub enum Picture3DContext<C> {
         /// Additional data per child for the case of this a root of 3D hierarchy.
         root_data: Option<Vec<C>>,
         /// The spatial node index of an "ancestor" element, i.e. one
-        /// that establishes the transformed element’s containing block.
+        /// that establishes the transformed element's containing block.
         ///
         /// See CSS spec draft for more details:
         /// https://drafts.csswg.org/css-transforms-2/#accumulated-3d-transformation-matrix-computation