chore(deps): update utxorpc-spec to v0.15 (#568)

Author: scarmuega

pallas-utxorpc/Cargo.toml

@@ -12,7 +12,7 @@ authors = ["Santiago Carmuega <[email protected]>"]
 
 [dependencies]
 # utxorpc-spec = { path = "../../../utxorpc/spec/gen/rust" }
-utxorpc-spec = { version = "0.14.0" }
+utxorpc-spec = { version = "0.15.0" }
 
 pallas-traverse = { version = "=0.31.0", path = "../pallas-traverse" }
 pallas-primitives = { version = "=0.31.0", path = "../pallas-primitives" }