message: docs: fix alpha_spaces rule example
diff: @@ -103,7 +103,7 @@ The field under validation may contain alphabetic characters or spaces.
  <RuleDemo rule="alpha_spaces" />
  ```vue
  -<ValidationProvider rules="alpha_num" v-slot="{ errors }">
  +<ValidationProvider rules="alpha_spaces" v-slot="{ errors }">
  <input v-model="value" type="text">
  <span>{{ errors[0] }}</span>
  </ValidationProvider>
  