Stop inline math in pages titles from disappearing
Stop inline math in pages titles from disappearing

closes LS-1716
flag=inline_math_everywhere

The pages index page had some CSS that caused MathJax typeset equations
in page titles to be hidden. The issue is only apparent if MathJax
is generating HTML and not SVG. Robin gets the HTML, while I get SVG
though I don't understand why. Anyway be aware of that.

test plan:
  - have a Page with inline LaTeX in the title (e.g. "math: \(y = x^2\)")
  - have a Page with a really long title
  - on the index page:
    > expect the equation to show up on the same line as the adjacent
      text
    > expect the really long title to be truncated with an ellipsis

Change-Id: I2ee71cdb323e0174c35028c70cd4aba48b4800e5
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/255501
Reviewed-by: Jackson Howe <318c10a818c1b1f2ec50cdcb1827b2c6c5ebd7dc@instructure.com>
Product-Review: Ed Schiebel <0ca8a83847a5889cf05cb219c0ab09f6b646243b@instructure.com>
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
QA-Review: Robin Kuss <0b206b54367b2de0334896ea45826f0e3194bd35@instructure.com>

sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms