Fix tests that were intermittently failing in CI

These tests have been failing intermittently in CI for about a year
now but until now had been unable to reproduce locally. For some
unknown reason (suspect dependency updates) they became consistently
reproducible locally this week, but were consistently passing in CI
:shrug:

Ensure all expected API calls are mocked for the error cases in the
affected tests so that they behave predictably.

src/containers/HeaderBarContent/HeaderBarContent.test.jsx

@@ -136,6 +136,7 @@ describe('HeaderBarContent', () => {
     const tenantNamespace2 = 'fake_tenantNamespace2';
     const path = '/namespaces/:namespace/fake/path';
     const selectNamespace = vi.fn();
+    vi.spyOn(API, 'useNamespaces').mockImplementation(() => []);
     vi.spyOn(API, 'useTenantNamespaces').mockImplementation(() => [
       tenantNamespace1,
       tenantNamespace2

src/containers/PipelineRun/PipelineRun.test.jsx

@@ -16,10 +16,11 @@ import { createIntl } from 'react-intl';
 import { paths, urls } from '@tektoncd/dashboard-utils';
 
 import { renderWithRouter } from '../../utils/test';
+import * as ClusterTasksAPI from '../../api/clusterTasks';
 import * as PipelineRunsAPI from '../../api/pipelineRuns';
+import * as PipelinesAPI from '../../api/pipelines';
 import * as TaskRunsAPI from '../../api/taskRuns';
 import * as TasksAPI from '../../api/tasks';
-import * as ClusterTasksAPI from '../../api/clusterTasks';
 import { PipelineRunContainer } from './PipelineRun';
 
 const intl = createIntl({
@@ -55,6 +56,22 @@ it('PipelineRunContainer renders not found state', async () => {
     data: null,
     error: null
   }));
+  vi.spyOn(TaskRunsAPI, 'useTaskRuns').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(TasksAPI, 'useTasks').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(ClusterTasksAPI, 'useClusterTasks').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(PipelinesAPI, 'usePipeline').mockImplementation(() => ({
+    data: null,
+    error: null
+  }));
 
   const { findByText } = renderWithRouter(
     <PipelineRunContainer intl={intl} />,
@@ -73,6 +90,22 @@ it('PipelineRunContainer renders error state', async () => {
     data: null,
     error: 'some error'
   }));
+  vi.spyOn(TaskRunsAPI, 'useTaskRuns').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(TasksAPI, 'useTasks').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(ClusterTasksAPI, 'useClusterTasks').mockImplementation(() => ({
+    data: [],
+    error: null
+  }));
+  vi.spyOn(PipelinesAPI, 'usePipeline').mockImplementation(() => ({
+    data: null,
+    error: null
+  }));
 
   const { findByText } = renderWithRouter(
     <PipelineRunContainer intl={intl} />,