consensus/parlia: explain turnterm in comments

consensus/parlia/snapshot.go

@@ -44,7 +44,7 @@ type Snapshot struct {
 
 	Number           uint64                            `json:"number"`                // Block number where the snapshot was created
 	Hash             common.Hash                       `json:"hash"`                  // Block hash where the snapshot was created
-	TurnTerm         uint64                            `json:"turn_term"`             // The consecutive number of blocks a validator receives priority for block production
+	TurnTerm         uint64                            `json:"turn_term"`             // Term of `turn`, meaning the consecutive number of blocks a validator receives priority for block production
 	Validators       map[common.Address]*ValidatorInfo `json:"validators"`            // Set of authorized validators at this moment
 	Recents          map[uint64]common.Address         `json:"recents"`               // Set of recent validators for spam protections
 	RecentForkHashes map[uint64]string                 `json:"recent_fork_hashes"`    // Set of recent forkHash