Fix broken backslash search 🎉

Author: cee-chen

src/components/basic_table/in_memory_table.test.tsx

@@ -1440,7 +1440,8 @@ describe('EuiInMemoryTable', () => {
 
   describe('text search format', () => {
     it('allows searching for any text with special characters in it', () => {
-      const specialCharacterSearch = '!@#$%^&*(){}+=-_hello:world"`<>?/👋~.,;|';
+      const specialCharacterSearch =
+        '!@#$%^&*(){}+=-_hello:world"`<>?/👋~.,;|\\';
       const items = [
         { title: specialCharacterSearch },
         { title: 'no special characters' },

src/components/basic_table/in_memory_table.tsx

@@ -541,7 +541,7 @@ export class EuiInMemoryTable<T> extends Component<
   // Alternative to onQueryChange - allows consumers to specify they want the
   // search bar to ignore EQL syntax and only use the searchbar for plain text
   onPlainTextSearch = (searchValue: string) => {
-    const escapedQueryText = searchValue.replaceAll('"', '\\"');
+    const escapedQueryText = searchValue.replace(/["\\]/g, '\\$&');
     const finalQuery = `"${escapedQueryText}"`;
     this.setState({
       query: EuiSearchBar.Query.parse(finalQuery),