Fix warnings and code cleanup/fixes (#13570)

Content.Shared/Humanoid/HumanoidVisualLayersExtension.cs

@@ -74,7 +74,6 @@ namespace Content.Shared.Humanoid
                     // use the Sublayers method to hide the rest of the parts,
                     // if that's what you're looking for
                     return HumanoidVisualLayers.Head;
-                    break;
                 case BodyPartType.Arm:
                     switch (part.Symmetry)
                     {

Content.Shared/Humanoid/Markings/Marking.cs

@@ -73,17 +73,15 @@ namespace Content.Shared.Humanoid.Markings
                 return 1;
             }
 
-            return MarkingId.CompareTo(marking.MarkingId);
+            return string.Compare(MarkingId, marking.MarkingId, StringComparison.Ordinal);
         }
 
         public int CompareTo(string? markingId)
         {
             if (markingId == null)
-            {
                 return 1;
-            }
 
-            return MarkingId.CompareTo(markingId);
+            return string.Compare(MarkingId, markingId, StringComparison.Ordinal);
         }
 
         public bool Equals(Marking? other)

Content.Shared/Humanoid/Prototypes/SpeciesPrototype.cs

@@ -94,17 +94,17 @@ public sealed class SpeciesPrototype : IPrototype
     public SpeciesNaming Naming { get; } = SpeciesNaming.FirstLast;
 
     [DataField("sexes")]
-    public List<Sex> Sexes { get; } = new List<Sex>(){ Sex.Male, Sex.Female };
+    public List<Sex> Sexes { get; } = new() { Sex.Male, Sex.Female };
 
     /// <summary>
     ///     Characters younger than this are too young to be hired by Nanotrasen.
-    /// <summary>
+    /// </summary>
     [DataField("minAge")]
     public int MinAge = 18;
 
     /// <summary>
     ///     Characters younger than this appear young.
-    /// <summary>
+    /// </summary>
     [DataField("youngAge")]
     public int YoungAge = 30;
 
@@ -117,7 +117,7 @@ public sealed class SpeciesPrototype : IPrototype
     /// <summary>
     ///     Characters cannot be older than this. Only used for restrictions...
     ///     although imagine if ghosts could age people WYCI...
-    /// <summary>
+    /// </summary>
     [DataField("maxAge")]
     public int MaxAge = 120;
 }
@@ -126,5 +126,5 @@ public enum SpeciesNaming : byte
 {
     FirstLast,
     FirstDashFirst,
-    TheFirstofLast
+    TheFirstofLast,
 }