* feat[contracts]: congestion price oracle

* chore: add changeset

* contracts: gas price oracle (#917)

* contracts: gas price oracle

* tests: update

* fees: fix tests

* contracts: simplify gas price oracle

* lint: fix

* test: execution price is at the 1st storage slot

* chore: rename predeploy to GasPriceOracle

* chore: rename gas price oracle test name
Co-authored-by: Mark Tyneway <mark.tyneway@gmail.com>
Co-authored-by: Georgios Konstantopoulos <me@gakonst.com>