Add Rootstock chainId

[ahsan-javaiid]

Description

This PR adds Rootstock chain id to this core sdk as integration proposal for Rootstock with Uniswap is under review.

Reason

To continue with rootstock integration in other Uniswap repos the chainId needs to be supported by sdk-core.

Any Questions

Feel free to ask any questions regarding the consideration of this pull request.

[ahsan-javaiid]

cc: @alepc253

[stale]

Is this still relevant? If so, what is blocking it? Is there anything you can do to help move it forward?

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[alepc253]

Yes, this is still relevant

[stale]

Is this still relevant? If so, what is blocking it? Is there anything you can do to help move it forward?

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[alepc253]

Yes, it is (and it should be quite easy to review and merge).

[stale]

Is this still relevant? If so, what is blocking it? Is there anything you can do to help move it forward?

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[alepc253]

Yes, still waiting for review and merge