Split repo move tests

The test to move from Gitaly to Gitaly Cluster wasn't running
because the Praefect scenario excludes orchestrated tests. However,
that scenario is intended to run all tests on an instance with
Praefect as storage, so it's fine to include this repo move test.

On the other hand, the repository storage scenario is like other
orchestrated tests, so the test needs the :orchestrated tag

qa/qa/specs/features/api/3_create/repository/changing_repository_storage_spec.rb

@@ -2,7 +2,7 @@
 
 module QA
   context 'Create' do
-    describe 'Changing Gitaly repository storage', :orchestrated, :requires_admin do
+    describe 'Changing Gitaly repository storage', :requires_admin do
       shared_examples 'repository storage move' do
         it 'confirms a `finished` status after moving project repository storage' do
           expect(project).to have_file('README.md')
@@ -24,7 +24,7 @@ module QA
         end
       end
 
-      context 'when moving from one Gitaly storage to another', :repository_storage do
+      context 'when moving from one Gitaly storage to another', :orchestrated, :repository_storage do
         let(:project) do
           Resource::Project.fabricate_via_api! do |project|
             project.name = 'repo-storage-move-status'
@@ -36,6 +36,8 @@ module QA
         it_behaves_like 'repository storage move'
       end
 
+      # Note: This test doesn't have the :orchestrated tag because it runs in the Test::Integration::Praefect
+      # scenario with other tests that aren't considered orchestrated.
       context 'when moving from Gitaly to Gitaly Cluster', :requires_praefect do
         let(:project) do
           Resource::Project.fabricate_via_api! do |project|