Chances of triggering effects (#27056)

* electrocution

* slippery

* flashibg

* Update SlipperyComponent.cs

* Update SlipperySystem.cs

Content.Server/Electrocution/ElectrocutionSystem.cs

@@ -213,6 +213,9 @@ public sealed class ElectrocutionSystem : SharedElectrocutionSystem
         if (!IsPowered(uid, electrified, transform))
             return false;
 
+        if (!_random.Prob(electrified.Probability))
+            return false;
+
         EnsureComp<ActivatedElectrifiedComponent>(uid);
         _appearance.SetData(uid, ElectrifiedVisuals.IsPowered, true);