## Is your feature request related to a problem?

As a team accumulates data, they will have events/properties that are no longer in use that clutter their app.

Example from our team:
![image](https://user-images.githubusercontent.com/148820/143202334-42d73ab6-13be-4661-ba7a-83c86788b9e8.png)


## Describe the solution you'd like

Under event/properties stats allow 'hiding' events/properties from view.

## Describe alternatives you've considered

Alternatively, go the route of "verified" events/properties (as He@p) does - show those first. See also https://help.heap.io/category/heap-administration/data-governance/

## Additional context

Note: Existing reports, etc should still work well even with 'removed' events/properties.

Related: https://github.com/PostHog/posthog/issues/7126

#### *Thank you* for your feature request – we love each and every one!

posthog/api/test/test_property_definition.py
[(r["name"], r["is_seen_on_filtered_events"]) for r in response.json()["results"]], [("first_visit", True)]
        )
    def test_person_property_filter(self):
        PropertyDefinition.objects.create(
            team=self.team, name="event property", property_type="String", type=PropertyDefinition.Type.EVENT
        )
        PropertyDefinition.objects.create(
            team=self.team, name="person property", property_type="String", type=PropertyDefinition.Type.PERSON
        )
        PropertyDefinition.objects.create(
            team=self.team, name="$initial_referrer", property_type="String", type=PropertyDefinition.Type.PERSON
        )  
        PropertyDefinition.objects.create(
            team=self.team, name="another", property_type="String", type=PropertyDefinition.Type.PERSON
        )
        response = self.client.get(f"/api/projects/{self.team.pk}/property_definitions/?type=person")
        self.assertEqual(response.status_code, status.HTTP_200_OK)
        self.assertEqual(
            [row["name"] for row in response.json()["results"]], ["$initial_referrer", "another", "person property"]
        )
        response = self.client.get(f"/api/projects/{self.team.pk}/property_definitions/?type=person&search=prop")
        self.assertEqual(response.status_code, status.HTTP_200_OK)
        self.assertEqual([row["name"] for row in response.json()["results"]], ["person property"])
        response = self.client.get(f"/api/projects/{self.team.pk}/property_definitions/?search=prop")
        self.assertEqual(response.status_code, status.HTTP_200_OK)
        self.assertEqual([row["name"] for row in response.json()["results"]], ["event property"])
    def test_group_property_filter(self):
        PropertyDefinition.objects.create(
            team=self.team,
            name="group1 property",