Update bad_extensions.rs (#834)

* Update bad_extensions.rs

Extensions are interchangeable. mp4 files being flagged as bad extensions of m4v. Apologies if they are in the wrong order.

* Update bad_extensions.rs

Author: OMEGARAZER

czkawka_core/src/bad_extensions.rs

@@ -83,6 +83,7 @@ static WORKAROUNDS: &[(&str, &str)] = &[
     ("html", "ent"),      // Mingw
     ("html", "md"),       // Markdown
     ("jpg", "jfif"),      // Photo format
+    ("m4v", "mp4"),       // m4v and mp4 are interchangable
     ("mobi", "azw3"),     // Ebook format
     ("mpg", "vob"),       // Weddings in parts have usually vob extension
     ("obj", "bin"),       // Multiple apps, Czkawka, Nvidia, Windows