Feature/nat 328 site names should be validated

gso/utils/helpers.py

@@ -187,10 +187,9 @@ def validate_site_name(site_name: str) -> str:
     The site name must consist of three uppercase letters (A-Z) followed by an optional single digit (0-9).
     """
     pattern = re.compile(r"^[A-Z]{3}[0-9]?$")
-    if pattern.match(site_name):
-        return site_name
-    else:
+    if not pattern.match(site_name):
         raise ValueError(
             "Enter a valid site name. It must consist of three uppercase letters (A-Z) followed by an optional single "
             "digit (0-9)."
         )
+    return site_name