Get repository from release url if given (#377)

Author: blink1073

jupyter_releaser/util.py

@@ -490,7 +490,12 @@ def prepare_environment():
     action scripts."""
     # Set up env variables
     if not os.environ.get("RH_REPOSITORY"):
-        os.environ["RH_REPOSITORY"] = os.environ["GITHUB_REPOSITORY"]
+        if os.environ.get("RH_RELEASE_URL"):
+            match = parse_release_url(os.environ["RH_RELEASE_URL"])
+            owner, repo = match["owner"], match["repo"]
+            os.environ["RH_REPOSITORY"] = f"{owner}/{repo}"
+        else:
+            os.environ["RH_REPOSITORY"] = os.environ["GITHUB_REPOSITORY"]
     if not os.environ.get("RH_REF"):
         os.environ["RH_REF"] = os.environ["GITHUB_REF"]