Add fredmello@ to module_installer OWNERS

For //src/components/module_installer/OWNERS.

Bug: None
Change-Id: I514d999285073fca97683f70eb03bb8d31d089d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1838296
Commit-Queue: Peter Wen <wnwen@chromium.org>
Commit-Queue: Tibor Goldschwendt <tiborg@chromium.org>
Auto-Submit: Peter Wen <wnwen@chromium.org>
Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702551}

components/module_installer/OWNERS

 agrieve@chromium.org
+fredmello@chromium.org
 tiborg@chromium.org
 wnwen@chromium.org
+
 # COMPONENT: Mobile>FeatureModules