MRESOLVER-377 makes several metadata related Maven IT fail

Change MRESOLVER-377 most probably altered how Maven -U and other CLI options (and possibly settings) is applied, and now is not applied to metadata.

Failed (and possibly related) ITs:

• MavenITmng4554PluginPrefixMappingUpdateTest.testitRefetched
• MavenITmng4433ForceParentSnapshotUpdateTest.testit
• MavenITmng5064SuppressSnapshotUpdatesTest.testit
• MavenITmng4745PluginVersionUpdateTest.testitForceUpdate
• MavenITmng4679SnapshotUpdateInPluginTest.testit
• MavenITmng4554PluginPrefixMappingUpdateTest.testitForcedUpdate
• MavenITmng4482ForcePluginSnapshotUpdateTest.testit
• MavenITmng4361ForceDependencySnapshotUpdateTest.testit
• MavenITmng4326LocalSnapshotSuppressesRemoteCheckTest.testit

Problem: the original change was kinda half-baked. Proper solution: Resolver internally should fully split artifact and metadata policies, while it should leave on "surface" (session iface and default imple) getter/setter for apps that does not want to distinguish between the two (whether as they are legacy, or intentionally).