Move WIP as low as possible but still above unresolved discussions

Also tests the (existing, untested) rebase state

app/assets/javascripts/vue_merge_request_widget/stores/get_state_key.js

@@ -11,12 +11,12 @@ export default function deviseState(data) {
     return stateKey.checking;
   } else if (data.has_conflicts) {
     return stateKey.conflicts;
-  } else if (data.work_in_progress) {
-    return stateKey.workInProgress;
   } else if (this.shouldBeRebased) {
     return stateKey.rebase;
   } else if (this.onlyAllowMergeIfPipelineSucceeds && this.isPipelineFailed) {
     return stateKey.pipelineFailed;
+  } else if (data.work_in_progress) {
+    return stateKey.workInProgress;
   } else if (this.hasMergeableDiscussionsState) {
     return stateKey.unresolvedDiscussions;
   } else if (this.isPipelineBlocked) {

spec/frontend/vue_mr_widget/stores/get_state_key_spec.js

@@ -49,14 +49,18 @@ describe('getStateKey', () => {
 
     expect(bound()).toEqual('unresolvedDiscussions');
 
+    data.work_in_progress = true;
+
+    expect(bound()).toEqual('workInProgress');
+
     context.onlyAllowMergeIfPipelineSucceeds = true;
     context.isPipelineFailed = true;
 
     expect(bound()).toEqual('pipelineFailed');
 
-    data.work_in_progress = true;
+    context.shouldBeRebased = true;
 
-    expect(bound()).toEqual('workInProgress');
+    expect(bound()).toEqual('rebase');
 
     data.has_conflicts = true;