[FIX] Use os.environ instead of os.putenv to set environment variables

bin/dup

@@ -21,7 +21,7 @@ def _set_env(index):
     for target_env_raw_name in target_environ_raw_names:
         env_value = os.getenv(target_env_raw_name)
         target_env_name = re.findall(r"^DST_\d+_(\w+)$", target_env_raw_name)[0]
-        os.putenv(target_env_name, env_value)
+        os.environ[target_env_name] = env_value
 
     # Expand shell commands from environment options
     # this resolves environment variables used in the string