Update lib/presentation/sign_up/screens/find_school_screen.dart

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: iloveuhyeon

lib/presentation/sign_up/screens/find_school_screen.dart

@@ -30,7 +30,7 @@ class FindSchoolScreen extends ConsumerWidget {
   Widget _schoolCard(
     SchoolInfoState school,
     SchoolInfoState? selectedSchool,
-    Function onTap,
+    VoidCallback onTap,
   ) {
     final isSelected = selectedSchool?.schoolName == school.schoolName;
     return GestureDetector(