Update the null object pattern example

Author: nemanjarogic

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/ApplicationRepository.cs

@@ -21,13 +21,8 @@ public ApplicationRepository()
         };
     }
 
-    public Application Find(Guid processId)
-    {
-        if (_installedApplications.TryGetValue(processId, out Application application))
-        {
-            return application;
-        }
-
-        return Application.Default;
-    }
-}
+    public Application Find(Guid processId) =>
+        _installedApplications.TryGetValue(processId, out var application)
+            ? application
+            : Application.Default;
+}

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/Applications/Common/Application.cs

@@ -10,7 +10,6 @@ protected Application(Guid processId)
     public static NullApplication Default { get; } = new();
 
     public abstract string Name { get; }
-
     public Guid ProcessId { get; }
 
     public virtual void Open() =>

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/Applications/Gmail.cs

@@ -10,4 +10,4 @@ public Gmail(Guid processId)
     }
 
     public override string Name => "Gmail";
-}
+}

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/Applications/NullApplication.cs

@@ -18,4 +18,4 @@ public override void Open()
     public override void Close()
     {
     }
-}
+}

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/Applications/SubwaySurfers.cs

@@ -10,4 +10,4 @@ public SubwaySurfers(Guid processId)
     }
 
     public override string Name => "Subway Surfers";
-}
+}

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/Applications/Youtube.cs

@@ -10,4 +10,4 @@ public Youtube(Guid processId)
     }
 
     public override string Name => "Youtube";
-}
+}

src/AdditionalPatterns/NullObject/NullObjectLibrary/SmartphoneApplicationExample/SmartphoneApplicationExecutor.cs

@@ -23,4 +23,4 @@ public static void Execute()
         youtube.Open();
         youtube.Close();
     }
-}
+}