Fix most rubocop issues (#2165)

* Run rubocop --autocorrect on app/, config/ and lib/, also manually fix some remaining style issues

* Run rubocop --autocorrect-all on db/

* Run rubocop --autocorrect-all on `spec/` and fix remaining issues

spec/policies/status_policy_spec.rb

@@ -83,14 +83,14 @@ RSpec.describe StatusPolicy, type: :model do
     end
 
     it 'denies access when local-only and the viewer is not logged in' do
-      allow(status).to receive(:local_only?) { true }
+      allow(status).to receive(:local_only?).and_return(true)
 
       expect(subject).to_not permit(nil, status)
     end
 
     it 'denies access when local-only and the viewer is from another domain' do
       viewer = Fabricate(:account, domain: 'remote-domain')
-      allow(status).to receive(:local_only?) { true }
+      allow(status).to receive(:local_only?).and_return(true)
       expect(subject).to_not permit(viewer, status)
     end
   end