* contracts-bedrock: create StaticConfig lib

* contracts-bedrock: fix StaticConfig

* contracts-bedrock: create diff tests for StaticConfig

* contracts-bedrock: rename gas paying token methods in StaticConfig

* contracts-bedrock: add decoding tests for StaticConfig

* contracts-bedrock: refactor encodeGasPayingToken

* contracts-bedrock: define uint256Type for differential testing

* contracts-bedrock: fix missing line in differential-testing

* contracts-bedrock: return packed in utils

* contracts-bedrock: define args as global vars in differential-testing

* contracts-bedrock: use Test instead of CommonTest in tests for StaticConfig

* contracts-bedrock: improve args for encodeGasPayingToken in diff testing

* contracts-bedrock: update sol version for StaticConfig to ^0.8.0