fix: avoid global mock clearing in EditTournamentForm tests

Replace mock.clearAllMocks() with mockFetch.mockClear() to only
clear the specific fetch mock without affecting global module mocks
used by other test files.

src/__tests__/EditTournamentForm.test.tsx

@@ -40,7 +40,8 @@ const mockTournament = {
 
 describe('EditTournamentForm', () => {
   beforeEach(() => {
-    mock.clearAllMocks()
+    // Only clear the specific mocks we create, not global module mocks
+    mockFetch.mockClear()
   })
 
   it('renders form with initial values', () => {