fix: extra newline after tables

src/MfGames.Markdown.Gemtext.Tests/TableTests.cs

@@ -70,6 +70,7 @@ namespace MfGames.Markdown.Gemini.Tests
                 "|   1 | 2   |  3  |",
                 "|   4 | 5   |  6  |",
                 "```",
+                "",
                 "");
             string actual = MarkdownGemtext.ToGemtext(input, pipeline);
 

src/MfGames.Markdown.Gemtext/Renderers/Gemtext/Blocks/TableRenderer.cs

@@ -77,6 +77,7 @@ namespace MfGames.Markdown.Gemtext.Renderers.Gemtext.Blocks
             if (!this.omitPreformat)
             {
                 renderer.WriteLine("```");
+                renderer.WriteLine();
             }
         }