Use after() to remove items added by test.

The test initally failed with a 500 when the `after` was added. Debugging narrowed it down to a missing default config.

getDefaultAgentConfigId errors if there isn't a default config.  The config is added by `setupIngestManager` which _was_ always called during plugin#start but is no longer.

We could add the setup call to the test/suite, but instead I changed AgentConfigService.delete to use ensureDefaultAgentConfig instead of getDefaultAgentConfigId.

ensureDefaultAgentConfig adds one if it's missing. The check in delete is to make sure we don't delete the default config. We can still do that and now we add a config if it wasn't already there (which seems like A Good Thing)

Author: John Schulz

x-pack/plugins/ingest_manager/server/services/agent_config.ts

@@ -336,7 +336,7 @@ class AgentConfigService {
       throw new Error('Agent configuration not found');
     }
 
-    const defaultConfigId = await this.getDefaultAgentConfigId(soClient);
+    const { id: defaultConfigId } = await this.ensureDefaultAgentConfig(soClient);
     if (id === defaultConfigId) {
       throw new Error('The default agent configuration cannot be deleted');
     }

x-pack/test/ingest_manager_api_integration/apis/package_config/get.ts

@@ -56,6 +56,24 @@ export default function (providerContext: FtrProviderContext) {
       packageConfigId = packageConfigResponse.item.id;
     });
 
+    after(async function () {
+      if (!server.enabled) {
+        return;
+      }
+
+      await supertest
+        .post(`/api/ingest_manager/agent_configs/delete`)
+        .set('kbn-xsrf', 'xxxx')
+        .send({ agentConfigId })
+        .expect(200);
+
+      await supertest
+        .post(`/api/ingest_manager/package_configs/delete`)
+        .set('kbn-xsrf', 'xxxx')
+        .send({ packageConfigIds: [packageConfigId] })
+        .expect(200);
+    });
+
     it('should succeed with a valid id', async function () {
       const { body: apiResponse } = await supertest
         .get(`/api/ingest_manager/package_configs/${packageConfigId}`)