Address Gemini code review comments

Signed-off-by: Kyle Julian <38759683+kylejuliandev@users.noreply.github.com>

Author: kylejuliandev

src/OpenFeature/Model/ImmutableMetadata.cs

@@ -17,10 +17,7 @@ public sealed class ImmutableMetadata
     /// <value>
     ///   <c>true</c> if this instance is empty; otherwise, <c>false</c>.
     /// </value>
-    public bool IsEmpty
-    {
-        get { return this._metadata.Count == 0; }
-    }
+    public bool IsEmpty => this._metadata.Count == 0;
 
     /// <summary>
     /// Constructor for the <see cref="ImmutableMetadata"/> class.

test/OpenFeature.Tests/ImmutableMetadataTest.cs

@@ -320,8 +320,7 @@ public void Count_ShouldReturnCountOfMetadata()
     public void IsEmpty_ShouldReturnTrue()
     {
         // Arrange
-        var metadata = new Dictionary<string, object>();
-        var flagMetadata = new ImmutableMetadata(metadata);
+        var flagMetadata = new ImmutableMetadata();
 
         // Act
         var result = flagMetadata.IsEmpty;