What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• It's submitted to the main branch for v2.x (or to a previous version branch)
• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)
• All tests are passing: https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#development-setup
• New/updated tests are included

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

Other information:

In v2.7 (for now I'm using, it's 2.7.14), when using defineComponent with props, method-based emits and setup like the code snippet below:

defineComponent({
  props: {
    foo: Number
  },
  emits: {
    'update:foo'(value: number) {}
  },
  setup(_, { emit }) {
    emit('update:foo', 123) // OK
    emit('update:foo', '123') // expect error, but passed
    emit('bar') // expect error, but passed
  }
})

the second and the third emit call in setup won't raise any TypeScript type-check errors.

However, if I change emits to using arrow functions like this:

defineComponent({
  props: {
    foo: Number
  },
  emits: {
-   'update:foo'(value: number) {}
+   'update:foo': (value: number) => {}
  },
  setup(_, { emit }) {
    emit('update:foo', 123) // OK
    emit('update:foo', '123') // error is raised as expected
    emit('bar') // error is raised as expected
  }
})

This PR fixes this by removing the Props generic from ComponentOptionsWithProps. In Overload 3 of defineComponent, props is always defined so there's no need to check if props is defined or not by using HasDefined type, then we inlined ExtractPropTypes<PropsOptions> (the default type of the removed Props generic).