Fail if input not recognised

entrypoint.py

@@ -49,8 +49,10 @@ def github_output(key, value):
 latest_beta = all_beta[-1]
 latest_rc = all_rc[-1]
 
-version_to_resolve = os.getenv("INPUT_VERSION_TO_RESOLVE", "")
-if version_to_resolve in ["stable", "current"]:
+version_to_resolve = os.getenv("INPUT_VERSION_TO_RESOLVE", "").strip()
+if version_to_resolve == "":
+    resolved_version = ""
+elif version_to_resolve in ["stable", "current"]:
     resolved_version = latest_stable
 elif version_to_resolve == "alpha":
     resolved_version = latest_alpha
@@ -59,7 +61,7 @@ def github_output(key, value):
 elif version_to_resolve in ["release-candidate", "rc"]:
     resolved_version = latest_rc
 else:
-    resolved_version = ""
+    raise Exception("Unrecognised `version-to-resolve` input value. Has to be one of [`stable`, `alpha`, `beta`, `rc`]")
 
 github_output(key="latest-stable", value=latest_stable)
 github_output(key="latest-alpha", value=latest_alpha)