Update gov/proposals/v0 namespace key size comment for clarity

Author: joaosreis

scls-cardano/cddl-src/Cardano/SCLS/CDDL.hs

@@ -99,4 +99,4 @@ type instance Spec.NamespaceKeySize "entities/committee/v0" = 8
 type instance Spec.NamespaceKeySize "gov/committee/v0" = 8
 type instance Spec.NamespaceKeySize "gov/constitution/v0" = 8
 type instance Spec.NamespaceKeySize "gov/pparams/v0" = 4
-type instance Spec.NamespaceKeySize "gov/proposals/v0" = 34 -- 32 bytes txid+tx index + 2 bytes for proposal index
+type instance Spec.NamespaceKeySize "gov/proposals/v0" = 34 -- 28 bytes txid, 4 bytes tx index, 2 bytes for proposal index