[Synthetics] unskip previously flaky test (#205573)

## Summary

Unskips flaky tests.

Passed in stateful and serverless for 50 iterations.

Previous failures related to fleet integration package failures. The
logic for installing the synthetics integration via fleet was changed to
improve flakiness in #204273. Those changes have also impacted the
flakiness of these tests.

x-pack/test/api_integration/deployment_agnostic/apis/observability/synthetics/get_monitor.ts

@@ -25,8 +25,7 @@ import { PrivateLocationTestService } from '../../../services/synthetics_private
 import { getFixtureJson } from './helpers/get_fixture_json';
 
 export default function ({ getService }: DeploymentAgnosticFtrProviderContext) {
-  // Failing: See https://github.com/elastic/kibana/issues/204158
-  describe.skip('getSyntheticsMonitors', function () {
+  describe('getSyntheticsMonitors', function () {
     const supertest = getService('supertestWithoutAuth');
     const kibanaServer = getService('kibanaServer');
     const retry = getService('retry');
@@ -80,8 +79,7 @@ export default function ({ getService }: DeploymentAgnosticFtrProviderContext) {
       monitors = _monitors;
     });
 
-    // FLAKY: https://github.com/elastic/kibana/issues/204069
-    describe.skip('get many monitors', () => {
+    describe('get many monitors', () => {
       it('without params', async () => {
         const uuid = uuidv4();
         const [mon1, mon2] = await Promise.all(