Update README.md

Author: erihsu

README.md

@@ -262,7 +262,7 @@ Here is a (non exhaustive) list of known projects using nom:
 [Matroska (MKV)](https://github.com/rust-av/matroska)
 - Document formats:
 [TAR](https://github.com/Keruspe/tar-parser.rs),
-[GZ](https://github.com/nharward/nom-gzip)
+[GZ](https://github.com/nharward/nom-gzip),
 [GDSII](https://github.com/erihsu/gds2-io)
 - Cryptographic formats:
 [X.509](https://github.com/rusticata/x509-parser)