ISTWCMS-4535 Change assertFieldById() to assertSession()->fieldExists()

Change record:
https://www.drupal.org/node/3129738

tests/src/Functional/UwWcmsBasicTest.php

@@ -1093,7 +1093,7 @@ class UwWcmsBasicTest extends BrowserTestBase {
     foreach ($types as $type) {
       $this->drupalGet('node/add/' . $type);
       $this->assertSession()->statusCodeEquals(200);
-      $this->assertFieldById('edit-field-uw-meta-description-0-value');
+      $this->assertSession()->fieldExists('edit-field-uw-meta-description-0-value');
       $this->assertSession()->buttonExists('edit-field-uw-meta-image-open-button');
     }
   }
@@ -1292,15 +1292,15 @@ class UwWcmsBasicTest extends BrowserTestBase {
 
     // Test timeline Step 7: Check all fields and buttons of timeline block.
     $this->assertSession()->pageTextContains('Title');
-    $this->assertFieldById('edit-settings-label');
+    $this->assertSession()->fieldExists('edit-settings-label');
     $this->assertSession()->pageTextContains('Timeline style');
-    $this->assertFieldById('edit-settings-block-form-field-uw-timeline-style');
+    $this->assertSession()->fieldExists('edit-settings-block-form-field-uw-timeline-style');
     $this->assertSession()->pageTextContains('Timeline sort');
-    $this->assertFieldById('edit-settings-block-form-field-uw-timeline-sort');
+    $this->assertSession()->fieldExists('edit-settings-block-form-field-uw-timeline-sort');
     $this->assertSession()->pageTextContains('Date');
-    $this->assertFieldById('edit-settings-block-form-field-uw-timeline-0-subform-field-uw-timeline-date-0-value-date');
+    $this->assertSession()->fieldExists('edit-settings-block-form-field-uw-timeline-0-subform-field-uw-timeline-date-0-value-date');
     $this->assertSession()->pageTextContains('Headline');
-    $this->assertFieldById('edit-settings-block-form-field-uw-timeline-0-subform-field-uw-timeline-headline-0-value');
+    $this->assertSession()->fieldExists('edit-settings-block-form-field-uw-timeline-0-subform-field-uw-timeline-headline-0-value');
     $this->assertSession()->pageTextContains('One or both of the "Headline" and "Content" fields must be populated.');
     $this->assertSession()->pageTextContains('PHOTO');
     $this->assertSession()->buttonExists('Add media');