[9.2] [SharedUX] Replace feedback snippet positive footer icon (#239741) (#239860)

# Backport

This will backport the following commits from `main` to `9.2`:
- [[SharedUX] Replace feedback snippet positive footer icon
(#239741)](#239741)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Ángeles Martínez
Barrio","email":"[email protected]"},"sourceCommit":{"committedDate":"2025-10-21T08:31:23Z","message":"[SharedUX]
Replace feedback snippet positive footer icon (#239741)\n\n##
Summary\n\n- Replaced `happyFace` icon with `thumbUp` one as suggested
by @ek-so \n\n### Testing\n\n<img width=\"238\" height=\"125\"
alt=\"Screenshot 2025-10-20 at 16 30
20\"\nsrc=\"https://github.com/user-attachments/assets/e4742e06-149a-413f-b4eb-282adea1ddbc\"\n/>","sha":"abff0ea89356982603b7586343de6ac7b5770f33","branchLabelMapping":{"^v9.3.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","Team:SharedUX","backport:version","v9.2.0","v9.3.0"],"title":"[SharedUX]
Replace feedback snippet positive footer
icon","number":239741,"url":"https://github.com/elastic/kibana/pull/239741","mergeCommit":{"message":"[SharedUX]
Replace feedback snippet positive footer icon (#239741)\n\n##
Summary\n\n- Replaced `happyFace` icon with `thumbUp` one as suggested
by @ek-so \n\n### Testing\n\n<img width=\"238\" height=\"125\"
alt=\"Screenshot 2025-10-20 at 16 30
20\"\nsrc=\"https://github.com/user-attachments/assets/e4742e06-149a-413f-b4eb-282adea1ddbc\"\n/>","sha":"abff0ea89356982603b7586343de6ac7b5770f33"}},"sourceBranch":"main","suggestedTargetBranches":["9.2"],"targetPullRequestStates":[{"branch":"9.2","label":"v9.2.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"main","label":"v9.3.0","branchLabelMappingKey":"^v9.3.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/239741","number":239741,"mergeCommit":{"message":"[SharedUX]
Replace feedback snippet positive footer icon (#239741)\n\n##
Summary\n\n- Replaced `happyFace` icon with `thumbUp` one as suggested
by @ek-so \n\n### Testing\n\n<img width=\"238\" height=\"125\"
alt=\"Screenshot 2025-10-20 at 16 30
20\"\nsrc=\"https://github.com/user-attachments/assets/e4742e06-149a-413f-b4eb-282adea1ddbc\"\n/>","sha":"abff0ea89356982603b7586343de6ac7b5770f33"}}]}]
BACKPORT-->

Co-authored-by: Ángeles Martínez Barrio <[email protected]>

Author: kibanamachine

src/platform/packages/shared/shared-ux/feedback_snippet/src/__snapshots__/feedback_panel.test.tsx.snap

@@ -50,13 +50,6 @@ const thumbDownIconLabel = i18n.translate(
   }
 );
 
-const faceHappyIconLabel = i18n.translate(
-  'sharedUXPackages.feedbackSnippet.feedbackPanel.faceHappyIconLabel',
-  {
-    defaultMessage: 'Happy face',
-  }
-);
-
 /**
  * A panel to gather user feedback.
  * There are 3 available views:
@@ -139,10 +132,10 @@ export const FeedbackPanel = ({
     <EuiFlexItem grow={false}>
       <EuiIcon
         data-test-subj="feedbackSnippetPanelPositiveIcon"
-        type="faceHappy"
+        type="thumbUp"
         color="success"
         size="l"
-        aria-label={faceHappyIconLabel}
+        aria-label={thumbUpIconLabel}
       />
     </EuiFlexItem>
   );