blm: remove reference to collab summit (#3333)

The event has passed

locale/en/black-lives-matter.md

@@ -156,13 +156,6 @@ We will work with any Black community member who wishes to contribute to
 Node.js. Please contact us at [blacklivesmatter@nodejs.org](mailto:blacklivesmatter@nodejs.org)
 or [@nodejs](https://twitter.com/nodejs) on Twitter with any questions.
 
-We have an upcoming free online [collaboration summit](https://github.com/openjs-foundation/summit#upcoming-events).
-There are [many different sessions](https://github.com/openjs-foundation/summit/issues?q=is%3Aissue+is%3Aopen+label%3A%22Session+Proposal%22)
-across various [OpenJS projects](https://openjsf.org/projects/), including Node.js.
-We have an [orientation guide](https://github.com/openjs-foundation/summit/blob/master/2020-06-23-Austin/orientation.md)
-to help you figure out how you might want to take part. If you have any questions or
-want to talk about anything, please reach out to [blacklivesmatter@nodejs.org](mailto:blacklivesmatter@nodejs.org).
-
 Moving forward we plan to offer ongoing support, mentorship, and sponsorship to
 help those from the Black community get involved in our project. We will
 also be analyzing our existing processes and governance to see what changes