Fix settings and password dict update

The update method on dict returns None, so we can not use the return value to set the variable as this will just delete the dictionary

ansible_runner/config/_base.py

@@ -147,7 +147,7 @@ def _prepare_env(self, runner_mode='pexpect'):
         self.runner_mode = runner_mode
         try:
             if self.settings and isinstance(self.settings, dict):
-                self.settings = self.settings.update(self.loader.load_file('env/settings', Mapping))
+                self.settings.update(self.loader.load_file('env/settings', Mapping))
             else:
                 self.settings = self.loader.load_file('env/settings', Mapping)
         except ConfigurationError:
@@ -157,7 +157,7 @@ def _prepare_env(self, runner_mode='pexpect'):
         if self.runner_mode == 'pexpect':
             try:
                 if self.passwords and isinstance(self.passwords, dict):
-                    self.passwords = self.passwords.update(self.loader.load_file('env/passwords', Mapping))
+                    self.passwords.update(self.loader.load_file('env/passwords', Mapping))
                 else:
                     self.passwords = self.passwords or self.loader.load_file('env/passwords', Mapping)
                 self.expect_passwords = {