added remapping for PER

Author: jourdanDunkley

remappings.txt

@@ -1,4 +1,5 @@
 flywheel/=lib/flywheel-v2/src/
 solidity-bytes-utils/=lib/solidity-bytes-utils/
 @openzeppelin=lib/openzeppelin-contracts/
-@pythnetwork/pyth-sdk-solidity/=lib/pyth-sdk-solidity/
+@pythnetwork/pyth-sdk-solidity/=lib/pyth-sdk-solidity/
+@pythnetwork/express-relay-sdk-solidity/=node_modules/@pythnetwork/express-relay-sdk-solidity