chore: deprecate nibiru 7210 chain env

[cgilbe27]

Deprecates 7210 and adds 6910

[github-actions]

You successfully submitted a PR! Due to the amount of PRs coming in: we will only look at PRs that the CI is happy with. We can also not hold your hand getting the CI green - just look how others that where merged did it and RTFM. So as long as there is any CI check that reports an error - no human will look at this. You might be able to ask for some support after supporting the project - e.g. by sending funds to lists.eth. When you fixed things after a requested change - then you also need to (re-)request a review.

[k-yang]

Chain ID 6910 is live and running for our testnet

[k-yang]

Hi, it seems that the build CI is still trying to look for chainId 7210 even though we marked that as deprecated. Should we just delete the file instead?

[cgilbe27]

@ligi Following up on this

[ligi]

you cannot delete chains - only mark them deprecated. This is important to prevent replay attacks

[k-yang]

Hi @ligi , we marked it as deprecated but then the build CI failed because it was expecting the old chainId (7210). What's the process for changing the chainId of a test network?

[k-yang]

Hi @ligi, please advise