fix(list item): Add overflow hidden

[cluelessjoe]

Resolves #1261
Done through mdc-typography-overflow-ellipsis mixin

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[cluelessjoe]

I signed the CLA
On top of it, screenshot before/after the bug fix:


I continue the discussion in #1261

[googlebot]

CLAs look good, thanks!

[lynnmercier]

You've got some lint errors still. Looks like it wants you to add an empty line between the @include and the next line

[codecov-io]

Codecov Report

Merging #1290 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1290   +/-   ##
=======================================
  Coverage   99.91%   99.91%           
=======================================
  Files          69       69           
  Lines        3381     3381           
  Branches      421      421           
=======================================
  Hits         3378     3378           
  Misses          3        3

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