Rider static analysis (#433)

* Non-accessed local variable

* Merge cast and type checks.

* StringComparison.Ordinal added for better culture support

* Supposed code improvement in launcher. Remove unused code.

* Update ExplosionHelper.cs

Unintentional change.

* Optimized Import

* Add Robust.Shared.Utility import where it was deleted

* Other random suggestion

* Improve my comment

Content.Client/GameObjects/Components/DamageableComponent.cs

@@ -20,9 +20,8 @@ namespace Content.Client.GameObjects
         {
             base.HandleComponentState(curState, nextState);
 
-            if(curState is DamageComponentState)
+            if(curState is DamageComponentState damagestate)
             {
-                var damagestate = (DamageComponentState)curState;
                 CurrentDamage = damagestate.CurrentDamage;
             }
         }