GitHub will automatically mention your issue in your own GitHub profile. This way, you can brag about filing an accepted issue in the CockroachDB repository.
We will try to acknowledge you in the PR description that fixes the bug, if/when we fix it directly as a result of your report. (We might not acknowledge you if the issue was already known for a long time, or if we came to it ourselves due to another project.)
If you also send a PR containing a fix, that adheres to our PR guidelines, and we accept it, you will be acknowledged in the next CockroachDB release notes.
Generally, Cockroach Labs does not provide monetary or in-kind rewards ('bounties') for reporting issues. Exceptions are extremely rare and limited to issues with an extremely high impact on Cockroach Labs' business.