[ObsUx][APM] Remove visual regression testing (#213787)

Relates to #208729 

## Summary

This PR removed the visual regression service map tests and the
screenshots used there. Unfortunately, we won't be able to use
screenshots for testing as it is not supported.

The tests should still pass and there shouldn't be an error in the CI
like:
   

![image](https://github.com/user-attachments/assets/f0e941a4-e197-49c5-bac4-fc9a2684f4b7)

x-pack/solutions/observability/plugins/apm/ui_tests/parallel_tests/sevice_map/service_map.spec.ts

@@ -25,13 +25,6 @@ test.describe('Service Map', { tag: ['@ess', '@svlOblt'] }, () => {
     await page.getByLabel('Zoom In').click();
     await page.getByTestId('centerServiceMap').click();
     await expect(page.getByTestId('serviceMap').getByLabel('Loading')).toBeHidden();
-    await page.evaluate(() => window.scrollTo(0, document.body.scrollHeight));
-    await page.getByTestId('serviceMap').click();
-    const serviceMapLocator = await page.getByTestId('serviceMap');
-    await expect(serviceMapLocator).toHaveScreenshot('service_map.png', {
-      animations: 'disabled',
-      maxDiffPixels: 10,
-    });
   });
 
   test('shows a detailed service map', async ({ page, pageObjects: { serviceMapPage } }) => {
@@ -42,13 +35,6 @@ test.describe('Service Map', { tag: ['@ess', '@svlOblt'] }, () => {
     await page.getByLabel('Zoom out').click();
     await page.getByTestId('centerServiceMap').click();
     await expect(page.getByTestId('serviceMap').getByLabel('Loading')).toBeHidden();
-    await page.evaluate(() => window.scrollTo(0, document.body.scrollHeight));
-    await page.getByTestId('serviceMap').click();
-    const serviceMapLocator = await page.getByTestId('serviceMap');
-    await expect(serviceMapLocator).toHaveScreenshot('detailed_service_map.png', {
-      animations: 'disabled',
-      maxDiffPixels: 10,
-    });
   });
 
   test('shows empty state when there is no data', async ({