Minor adjustments

Source/QuestPDF.DocumentationExamples/ImageExamples.cs

@@ -205,7 +205,7 @@ public class ImageExamples
     [Test]
     public void SharedImages()
     {
-        var image = Image.FromFile("Resources/checkbox.png");
+        using var image = Image.FromFile("Resources/checkbox.png");
         
         Document
             .Create(document =>

Source/QuestPDF.UnitTests/ImageTests.cs

@@ -163,7 +163,9 @@ namespace QuestPDF.UnitTests
         static DocumentImage GenerateDocumentImage(int width, int height)
         {
             var image = Placeholders.Image(width, height);
-            return DocumentImage.FromBinaryData(image);
+            var result = DocumentImage.FromBinaryData(image);
+            result.IsShared = false;
+            return result;
         }
     }
 }

Source/QuestPDF/Elements/Text/TextBlock.cs

@@ -48,6 +48,9 @@ namespace QuestPDF.Elements.Text
 
         ~TextBlock()
         {
+            if (Paragraph == null)
+                return;
+            
             this.WarnThatFinalizerIsReached();
             Dispose();
         }

Source/QuestPDF/Infrastructure/Image.cs

@@ -84,7 +84,7 @@ namespace QuestPDF.Infrastructure
         public static Image FromBinaryData(byte[] imageBytes)
         {
             using var imageData = SkData.FromBinary(imageBytes);
-            return StaticImageCache.DecodeImage(imageData, isShared: false);
+            return StaticImageCache.DecodeImage(imageData, isShared: true);
         }
 
         /// <summary>
@@ -105,7 +105,7 @@ namespace QuestPDF.Infrastructure
         public static Image FromStream(Stream stream)
         {
             using var imageData = SkData.FromStream(stream);
-            return StaticImageCache.DecodeImage(imageData, isShared: false);
+            return StaticImageCache.DecodeImage(imageData, isShared: true);
         }
 
         #endregion