cleanup model relationship references

app/Models/PirepComment.php

@@ -23,11 +23,11 @@ class PirepComment extends BaseModel
 
     public function pirep()
     {
-        return $this->belongsTo('App\Models\Pirep', 'pirep_id');
+        return $this->belongsTo(Pirep::class, 'pirep_id');
     }
 
     public function user()
     {
-        return $this->belongsTo('App\Models\User', 'user_id');
+        return $this->belongsTo(User::class, 'user_id');
     }
 }