Updated mediawiki/extensions
Project: mediawiki/extensions/ImageMetrics  691c3957e07a315d301d01292a86ec8b757a87cb

Fix ImageMetrics schema

https://meta.wikimedia.org/w/index.php?diff=10078363

Fixes two issues:
* some fields which were previously marked integer can have higher precision
* non-required numeric EventLogging fields are not happy with null

Change-Id: I7acba21690d6feb3af9e3f635d581cf242295d04