Apply suggestion from @nicoddemus

Author: nicoddemus

src/_pytest/python.py

@@ -913,7 +913,7 @@ def make_unique_parameterset_ids(self) -> list[str | _HiddenParam]:
                 # Keep only duplicates
                 duplicates = {k: v for k, v in duplicate_indexs.items() if len(v) > 1}
                 raise UsageError(f"""
-                    Because: require_unique_parameterset_ids is set, pytest won't
+                    Because --require-unique-paramset-ids given, pytest won't
                     attempt to generate unique IDs for parameter sets.
                     argument values: {self.parametersets}
                     argument names: {self.argnames}