Fix share modal copy embed code (elastic#204584)

## Summary

Closes elastic#204312

This PR removes an unnecessary function, that causes an infinite render
loop for visualisations.


## After


https://github.com/user-attachments/assets/259d238b-c1cf-4d74-bfca-1a6440d0f5cd

## How to test
- From the left side nav, click the `Visualize Library` menu item,
attempt to create a legacy visualisation, any one of choice and attempt
sharing said created visualisation clicking the copy embed code should
not result in any error but rather copy the embed code with the visual
feedback.

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src/plugins/share/public/components/tabs/embed/embed_content.test.tsx

@@ -18,12 +18,7 @@ describe('Share modal embed content tab', () => {
 
     beforeEach(() => {
       component = mountWithIntl(
-        <EmbedContent
-          isDirty={false}
-          objectType="dashboard"
-          setIsNotSaved={() => jest.fn()}
-          shareableUrl="/home#/"
-        />
+        <EmbedContent isDirty={false} objectType="dashboard" shareableUrl="/home#/" />
       );
     });
 

src/plugins/share/public/components/tabs/embed/embed_content.tsx

@@ -34,7 +34,6 @@ type EmbedProps = Pick<
   | 'objectType'
   | 'isDirty'
 > & {
-  setIsNotSaved: () => void;
   objectConfig?: ShareContextObjectTypeConfig;
 };
 
@@ -55,7 +54,6 @@ export const EmbedContent = ({
   shareableUrl,
   objectType,
   objectConfig = {},
-  setIsNotSaved,
   isDirty,
 }: EmbedProps) => {
   const isMounted = useMountedState();
@@ -67,10 +65,6 @@ export const EmbedContent = ({
   const [anonymousAccessParameters] = useState<AnonymousAccessState['accessURLParameters']>(null);
   const [usePublicUrl] = useState<boolean>(false);
 
-  useEffect(() => {
-    if (objectType !== 'dashboard') setIsNotSaved();
-  }, [url, setIsNotSaved, objectType]);
-
   const makeUrlEmbeddable = useCallback((tempUrl: string): string => {
     const embedParam = '?embed=true';
     const urlHasQueryString = tempUrl.indexOf('?') !== -1;

src/plugins/share/public/components/tabs/embed/index.tsx

@@ -8,35 +8,13 @@
  */
 
 import { i18n } from '@kbn/i18n';
-import React, { useCallback } from 'react';
+import React from 'react';
 import { type IModalTabDeclaration } from '@kbn/shared-ux-tabbed-modal';
 import { EmbedContent } from './embed_content';
 import { useShareTabsContext } from '../../context';
 
-const EMBED_TAB_ACTIONS = {
-  SET_EMBED_URL: 'SET_EMBED_URL',
-  SET_IS_NOT_SAVED: 'SET_IS_NOT_SAVED',
-};
-
 type IEmbedTab = IModalTabDeclaration<{ url: string; isNotSaved: boolean }>;
 
-const embedTabReducer: IEmbedTab['reducer'] = (state = { url: '', isNotSaved: false }, action) => {
-  switch (action.type) {
-    case EMBED_TAB_ACTIONS.SET_IS_NOT_SAVED:
-      return {
-        ...state,
-        isNotSaved: action.payload,
-      };
-    case EMBED_TAB_ACTIONS.SET_IS_NOT_SAVED:
-      return {
-        ...state,
-        isNotSaved: action.payload,
-      };
-    default:
-      return state;
-  }
-};
-
 const EmbedTabContent: NonNullable<IEmbedTab['content']> = ({ state, dispatch }) => {
   const {
     embedUrlParamExtensions,
@@ -47,13 +25,6 @@ const EmbedTabContent: NonNullable<IEmbedTab['content']> = ({ state, dispatch })
     isDirty,
   } = useShareTabsContext()!;
 
-  const setIsNotSaved = useCallback(() => {
-    dispatch({
-      type: EMBED_TAB_ACTIONS.SET_IS_NOT_SAVED,
-      payload: objectType === 'dashboard' ? isDirty : false,
-    });
-  }, [dispatch, objectType, isDirty]);
-
   return (
     <EmbedContent
       {...{
@@ -62,8 +33,6 @@ const EmbedTabContent: NonNullable<IEmbedTab['content']> = ({ state, dispatch })
         shareableUrl,
         objectType,
         objectConfig: objectTypeMeta?.config?.embed,
-        isNotSaved: state?.isNotSaved,
-        setIsNotSaved,
         isDirty,
       }}
     />
@@ -75,6 +44,5 @@ export const embedTab: IEmbedTab = {
   name: i18n.translate('share.contextMenu.embedCodeTab', {
     defaultMessage: 'Embed',
   }),
-  reducer: embedTabReducer,
   content: EmbedTabContent,
 };