test: standardize l10n mock usage in Signature.spec.ts

Signed-off-by: Vitor Mattos <1079143+vitormattos@users.noreply.github.com>

Author: vitormattos

src/tests/views/Account/partials/Signature.spec.ts

@@ -4,7 +4,6 @@
  */
 
 import { beforeAll, describe, expect, it, vi } from 'vitest'
-import { createL10nMock } from '../../../testHelpers/l10n.js'
 import { mount } from '@vue/test-utils'
 import type { VueWrapper } from '@vue/test-utils'
 
@@ -28,7 +27,7 @@ vi.mock('@nextcloud/dialogs', () => ({
 	showSuccess: vi.fn(),
 }))
 
-vi.mock('@nextcloud/l10n', () => createL10nMock())
+vi.mock('@nextcloud/l10n', () => globalThis.mockNextcloudL10n())
 
 type SignatureComponent = typeof import('../../../../views/Account/partials/Signature.vue').default