Update rollbar sponsor URL (encode#6791)

Author: lovelydinosaur

README.md

@@ -202,7 +202,7 @@ Please see the [security policy][security-policy].
 
 [sentry-url]: https://getsentry.com/welcome/
 [stream-url]: https://getstream.io/try-the-api/?utm_source=drf&utm_medium=banner&utm_campaign=drf
-[rollbar-url]: https://rollbar.com/
+[rollbar-url]: https://rollbar.com/?utm_source=django&utm_medium=sponsorship&utm_campaign=freetrial
 [cadre-url]: https://cadre.com/
 [kloudless-url]: https://hubs.ly/H0f30Lf0
 [esg-url]: https://software.esg-usa.com/

docs/index.md

@@ -76,7 +76,7 @@ continued development by **[signing up for a paid plan][funding]**.
 </ul>
 <div style="clear: both; padding-bottom: 20px;"></div>
 
-*Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry](https://getsentry.com/welcome/), [Stream](https://getstream.io/?utm_source=drf&utm_medium=banner&utm_campaign=drf), [ESG](https://software.esg-usa.com/), [Rollbar](https://rollbar.com), [Cadre](https://cadre.com), [Kloudless](https://hubs.ly/H0f30Lf0), and [Lights On Software](https://lightsonsoftware.com).*
+*Many thanks to all our [wonderful sponsors][sponsors], and in particular to our premium backers, [Sentry](https://getsentry.com/welcome/), [Stream](https://getstream.io/?utm_source=drf&utm_medium=banner&utm_campaign=drf), [ESG](https://software.esg-usa.com/), [Rollbar](https://rollbar.com/?utm_source=django&utm_medium=sponsorship&utm_campaign=freetrial), [Cadre](https://cadre.com), [Kloudless](https://hubs.ly/H0f30Lf0), and [Lights On Software](https://lightsonsoftware.com).*
 
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