buildstream-plugins: ignore Git tags containing *dev*

Tags containing `*dev*` on official BuildStream projects are for
pre-releases, and should not be included in the passthru updateScript.

This is needed after https://github.com/NixOS/nixpkgs/pull/493236 showed
a issue with the updateScript.

pkgs/development/python-modules/buildstream-plugins/default.nix

@@ -2,6 +2,7 @@
   lib,
   buildPythonPackage,
   fetchFromGitHub,
+  gitUpdater,
   setuptools,
   cython,
 }:
@@ -29,6 +30,10 @@ buildPythonPackage rec {
 
   pythonImportsCheck = [ "buildstream_plugins" ];
 
+  passthru.updateScript = gitUpdater {
+    ignoredVersions = "dev";
+  };
+
   meta = {
     description = "BuildStream plugins";
     homepage = "https://github.com/apache/buildstream-plugins";