Fix tests, tweak message

Author: mgedmin

src/check_python_versions/cli.py

@@ -127,7 +127,7 @@ def check_package(where: str = '.', *, print: PrintFn = print) -> bool:
 
     if not is_package(where):
         print("no setup.py or pyproject.toml -- not a Python package?")
-        print("you may want to try check-python-versions --allow-non-packages")
+        print("you may want to try --allow-non-packages")
         return False
 
     return True

tests/test_cli.py

@@ -86,8 +86,10 @@ def test_check_not_a_directory(tmp_path, capsys):
 
 def test_check_not_a_package(tmp_path, capsys):
     assert not cpv.check_package(tmp_path)
-    assert capsys.readouterr().out == 'no setup.py or pyproject.toml' \
-                                      ' -- not a Python package?\n'
+    assert capsys.readouterr().out == textwrap.dedent('''\
+        no setup.py or pyproject.toml -- not a Python package?
+        you may want to try --allow-non-packages
+    ''')
 
 
 def test_check_package(tmp_path):