Update packages/srt/srt.0.3.0/opam

Co-authored-by: Marcello Seri <[email protected]>

Author: toots

packages/srt/srt.0.3.0/opam

@@ -9,7 +9,7 @@ This package provides OCaml bindings to the C implementation library.
 """
 maintainer: ["The Savonet Team <[email protected]>"]
 authors: ["The Savonet Team <[email protected]>"]
-license: "GPL-2.0"
+license: "GPL-2.0-only"
 homepage: "https://github.com/savonet/ocaml-srt"
 bug-reports: "https://github.com/savonet/ocaml-srt/issues"
 depends: [