Renamed the Media section to "media-management"

This is to follow consistency with the members/users sections.

My gut feeling is that I'm off with this, and need to sanity check
with @madsrasmussen and @nielslyngsoe.

src/Umbraco.Web.UI.Client/src/packages/media/section.manifests.ts

@@ -12,7 +12,7 @@ const section: ManifestSection = {
 	weight: 500,
 	meta: {
 		label: 'Media',
-		pathname: 'media',
+		pathname: 'media-management',
 	},
 	conditions: [],
 };