Use correct ExecutionContext for check_inherents (#9483)

Before we used the `other` context, while we are actually either in the
import or sync context.

substrate/primitives/consensus/common/src/lib.rs

@@ -75,6 +75,16 @@ pub enum BlockOrigin {
 	File,
 }
 
+impl From<BlockOrigin> for sp_core::ExecutionContext {
+	fn from(origin: BlockOrigin) -> Self {
+		if origin == BlockOrigin::NetworkInitialSync {
+			sp_core::ExecutionContext::Syncing
+		} else {
+			sp_core::ExecutionContext::Importing
+		}
+	}
+}
+
 /// Environment for a Consensus instance.
 ///
 /// Creates proposer instance.