Fix data provider gas refund

[awfm9]

The state connector has a mechanism to refund data providers for transactions to the price provider, if the transactions succeed.

This used the nominal fee for a normal transaction of tokens as a baseline, which was 21k gas with a gas price of 225M. However, with the hard fork we did, the minimum gas price was reduced to 25M instead. This means that data provider submissions are now 9 times as expensive as they should be.

We need to implement a mechanism to transition to the new gas price as part of the next hard fork.