[ML] Transforms: Enable SLO transforms installer on CI (#165470)

## Summary

This enables the installer for SLO transforms on CI.

- For the `many_fields_transform` performance journey, it will then look
for the "Create transform" on top of the table instead of the "Create
your first transform" button. Command to test the performance journey:
`node scripts/run_performance.js --journey-path
x-pack/performance/journeys/many_fields_transform.ts --skip-warmup`
- For the functional tests that assert the empty transform list, this
adds a command to delete all transforms before running those tests.

x-pack/performance/journeys/many_fields_transform.ts

@@ -15,11 +15,11 @@ export const journey = new Journey({
   .step('Go to Transforms', async ({ page, kbnUrl, kibanaPage }) => {
     await page.goto(kbnUrl.get(`app/management/data/transform`));
     await kibanaPage.waitForHeader();
-    await page.waitForSelector(subj('transformCreateFirstButton'));
+    await page.waitForSelector(subj('transformButtonCreate'));
     await page.waitForSelector(subj('globalLoadingIndicator-hidden'));
   })
   .step('Go to data view selection', async ({ page }) => {
-    const createButtons = page.locator(subj('transformCreateFirstButton'));
+    const createButtons = page.locator(subj('transformButtonCreate'));
     await createButtons.first().click();
     await page.waitForSelector(subj('savedObjectsFinderTable'));
   })

x-pack/plugins/observability/server/services/slo/slo_installer.ts

@@ -22,7 +22,7 @@ export class DefaultSLOInstaller implements SLOInstaller {
   ) {}
 
   public async install() {
-    if (this.isInstalling || process.env.CI) {
+    if (this.isInstalling) {
       return;
     }
     this.isInstalling = true;

x-pack/plugins/transform/public/app/hooks/use_index_data.ts

@@ -310,6 +310,8 @@ export const useIndexData = (
   if (
     dataGrid.status === INDEX_STATUS.LOADED &&
     dataViewFields !== undefined &&
+    Array.isArray(histogramsForFieldsData) &&
+    histogramsForFieldsData.length > 0 &&
     loadIndexDataStartTime.current !== undefined
   ) {
     const loadIndexDataDuration = window.performance.now() - loadIndexDataStartTime.current;

x-pack/test/functional/apps/transform/permissions/full_transform_access.ts

@@ -17,6 +17,10 @@ export default function ({ getService }: FtrProviderContext) {
     describe('with no data loaded', function () {
       before(async () => {
         await transform.securityUI.loginAsTransformPowerUser();
+
+        // For this test to work, make sure there are no pre-existing transform present.
+        // For example, solutions might set up transforms automatically.
+        await transform.api.cleanTransformIndices();
       });
 
       after(async () => {

x-pack/test/functional/apps/transform/permissions/read_transform_access.ts

@@ -17,6 +17,10 @@ export default function ({ getService }: FtrProviderContext) {
     describe('with no data loaded', function () {
       before(async () => {
         await transform.securityUI.loginAsTransformViewer();
+
+        // For this test to work, make sure there are no pre-existing transform present.
+        // For example, solutions might set up transforms automatically.
+        await transform.api.cleanTransformIndices();
       });
 
       after(async () => {

x-pack/test/functional/apps/upgrade_assistant/deprecation_pages.ts

@@ -27,7 +27,7 @@ export default function upgradeAssistantFunctionalTests({
       try {
         /**
          * Trigger "Total shards" ES Upgrade readiness check
-         * the number of shards in the test cluster is 25-27
+         * the number of shards in the test cluster is 25-29
          * so 5 max shards per node should trigger this check
          * on both local and CI environments.
          */
@@ -53,7 +53,7 @@ export default function upgradeAssistantFunctionalTests({
             persistent: {
               cluster: {
                 // initial cluster setting from x-pack/test/functional/config.upgrade_assistant.js
-                max_shards_per_node: 27,
+                max_shards_per_node: 29,
               },
             },
           },

x-pack/test/functional/config.upgrade_assistant.ts

@@ -31,7 +31,7 @@ export default async function ({ readConfigFile }: FtrConfigProviderContext) {
         'cluster.routing.allocation.disk.threshold_enabled=true', // make sure disk thresholds are enabled for UA cluster testing
         'cluster.routing.allocation.disk.watermark.low=30%',
         'cluster.info.update.interval=10s',
-        'cluster.max_shards_per_node=27',
+        'cluster.max_shards_per_node=29',
       ],
     },
   };