Use 'new' expression in places where the type is evident for content (#2590)

* Content.Client

* Content.Benchmarks

* Content.IntegrationTests

* Content.Server

* Content.Server.Database

* Content.Shared

* Content.Tests

* Merge fixes

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.Client/GameObjects/Components/HandheldLightComponent.cs

@@ -42,12 +42,12 @@ namespace Content.Client.GameObjects.Components
 
             private float _timer;
 
-            private static readonly StyleBoxFlat _styleBoxLit = new StyleBoxFlat
+            private static readonly StyleBoxFlat _styleBoxLit = new()
             {
                 BackgroundColor = Color.Green
             };
 
-            private static readonly StyleBoxFlat _styleBoxUnlit = new StyleBoxFlat
+            private static readonly StyleBoxFlat _styleBoxUnlit = new()
             {
                 BackgroundColor = Color.Black
             };