Updated mediawiki/extensions
Project: mediawiki/extensions/Math  ee479e8e68ce62b9fe558742bb57df5cdda78ee9

Fix centering of PNG image in display mode.

Revert the mistake made in https://gerrit.wikimedia.org/r/#/c/139120.

Change-Id: I31420ba3ab1e1b47c3e7307ac4a9aca2a6a8223f