update townhall date
![DataHub](docs/imgs/datahub-logo.png)
-> :mega: Next DataHub town hall meeting on July 31st, 9am-10am PDT:
+> :mega: Next DataHub town hall meeting on August 20th, 9am-10am PDT:
> - [Signup sheet & questions](https://docs.google.com/spreadsheets/d/1hCTFQZnhYHAPa-DeIfyye4MlwmrY7GF4hBds5pTZJYM)
-> - VC link: https://linkedin.zoom.us/j/95617940722
+> - VC link (**NEW** we're using zoom!): https://linkedin.zoom.us/j/95617940722
> - Details and recordings of past meetings can be found [here](docs/townhalls.md)
> :sparkles: Latest Update:
