tests: Fix trailing whitespace and a blanket type-ignore

pytest.ini

@@ -27,4 +27,4 @@ log_cli_level=INFO
 #
 # Add directory to find the example branding.py (needed by bootloader.py) in ./stubs:
 # (Requires pytest >= 7.0.0):
-pythonpath=stubs
+pythonpath=stubs

pytype_runner.py

@@ -77,7 +77,7 @@ def run_pytype(command: List[str], branch_url: str, errorlog: TextIO, results):
     ok = True
     while ok:
         for key, _ in sel.select():
-            line = key.fileobj.readline()  # type: ignore
+            line = key.fileobj.readline()  # type: ignore[union-attr]
             if not line:
                 ok = False
                 break

tests/test_bootloader.py

@@ -19,15 +19,16 @@ def _test_cfg(self, cfg):
                                     universal_newlines=True)
 
             assert proc.stdout is not None  # for pyright, to ensure it is valid
+            # check the diff output, working around trailing whitespace issues
             self.assertEqual(proc.stdout.read(), '''5a6,13
 > if [ -s $prefix/grubenv ]; then
 > 	load_env
 > fi
-> 
+> ''' + '''
 > if [ -n "$override_entry" ]; then
 > 	set default=$override_entry
 > fi
-> 
+> ''' + '''
 ''')
             proc.stdout.close()
             proc.wait()