Fix empty CSS creation (microsoft#28566)

* Remove empty style declaration

* Change files

* Remove makeStyles import

* Update change/@fluentui-react-toolbar-3898461e-a785-43d9-9b44-149bb5a84e79.json

Co-authored-by: Makoto Morimoto <Humberto.Morimoto@microsoft.com>

---------

Co-authored-by: Ben Howell <48106640+behowell@users.noreply.github.com>
Co-authored-by: ling1726 <lingfangao@hotmail.com>
Co-authored-by: Makoto Morimoto <Humberto.Morimoto@microsoft.com>

change/@fluentui-react-toolbar-3898461e-a785-43d9-9b44-149bb5a84e79.json

@@ -0,0 +1,7 @@
+{
+  "type": "patch",
+  "comment": "fix: Remove empty makeStyles call.",
+  "packageName": "@fluentui/react-toolbar",
+  "email": "138819425+benlemmon-ms@users.noreply.github.com",
+  "dependentChangeType": "patch"
+}

packages/react-components/react-toolbar/src/components/ToolbarGroup/useToolbarGroupStyles.styles.ts

@@ -1,24 +1,16 @@
 import { SlotClassNames } from '@fluentui/react-utilities';
-import { makeStyles, mergeClasses } from '@griffel/react';
+import { mergeClasses } from '@griffel/react';
 import type { ToolbarGroupSlots, ToolbarGroupState } from './ToolbarGroup.types';
 
 export const toolbarGroupClassNames: SlotClassNames<ToolbarGroupSlots> = {
   root: 'fui-ToolbarGroup',
 };
 
-/**
- * Styles for the root slot
- */
-const useStyles = makeStyles({
-  root: {},
-});
-
 /**
  * Apply styling to the Toolbar slots based on the state
  */
 export const useToolbarGroupStyles_unstable = (state: ToolbarGroupState): ToolbarGroupState => {
-  const styles = useStyles();
-  state.root.className = mergeClasses(toolbarGroupClassNames.root, styles.root, state.root.className);
+  state.root.className = mergeClasses(toolbarGroupClassNames.root, state.root.className);
 
   return state;
 };