Fix some build warnings (#6832)

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Server/Medical/HealingSystem.cs

@@ -15,7 +15,6 @@ namespace Content.Server.Medical;
 
 public sealed class HealingSystem : EntitySystem
 {
-    [Dependency] private readonly ActionBlockerSystem _blocker = default!;
     [Dependency] private readonly AdminLogSystem _logs = default!;
     [Dependency] private readonly DamageableSystem _damageable = default!;
     [Dependency] private readonly BloodstreamSystem _bloodstreamSystem = default!;