Parsing out cover images (#513)

- Fixing workflow
- Adding test case

API.Tests/Parser/MangaParserTests.cs

@@ -1,4 +1,4 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 using API.Entities.Enums;
 using API.Parser;
 using Xunit;
@@ -407,6 +407,10 @@ namespace API.Tests.Parser
               FullFilePath = filepath, IsSpecial = false
             });
 
+            // If an image is cover exclusively, ignore it
+            filepath = @"E:\Manga\Seraph of the End\cover.png";
+            expected.Add(filepath, null);
+
 
             foreach (var file in expected.Keys)
             {