Update codeowners for txm clientwrappers

Author: dimriou

.github/CODEOWNERS

@@ -85,6 +85,7 @@ go.mod @smartcontractkit/core @smartcontractkit/foundations @smartcontractkit/co
 go.sum @smartcontractkit/core @smartcontractkit/foundations @smartcontractkit/core-solidity
 
 pkg/txm @dimriou @smartcontractkit/bix-framework @smartcontractkit/core
+pkg/txm/clientwrappers @dimriou @smartcontractkit/oev
 pkg/bindings @smartcontractkit/bix-framework
 pkg/config/toml/defaults @smartcontractkit/bix-framework
 pkg/logpoller @smartcontractkit/bix-framework