primitives: added serde feature (#14256)

serde feature added for:
- sp-statement-store
- sp-authority-discovery

substrate/primitives/authority-discovery/Cargo.toml

@@ -30,3 +30,8 @@ std = [
 	"sp-runtime/std",
 	"sp-std/std",
 ]
+serde = [
+	"scale-info/serde",
+	"sp-application-crypto/serde",
+	"sp-runtime/serde",
+]

substrate/primitives/statement-store/Cargo.toml

@@ -39,3 +39,9 @@ std = [
 	"thiserror",
 	"log",
 ]
+serde = [
+        "scale-info/serde",
+        "sp-application-crypto/serde",
+        "sp-core/serde",
+        "sp-runtime/serde",
+]