Upgrade restrictedpython to 4.0b7

[fabaff]

Description:

Changelog: https://github.com/zopefoundation/RestrictedPython/blob/master/docs/CHANGES.rst#40b7-2018-10-30

Example entry for configuration.yaml (if applicable):

python_script:

Test script:

entities = hass.states.entity_ids()

logger.info(entities)

2018-12-02 00:11:11 INFO (SyncWorker_12) [homeassistant.components.python_script] Executing list-entities.py: {}
2018-12-02 00:11:11 INFO (SyncWorker_12) [homeassistant.components.python_script.list-entities.py] ['sun.sun', 'sensor.wohnzimmer_temperatur', ... 'persistent_notification.config_entry_discovery']

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.

If the code communicates with devices, web services, or third-party tools:

• New dependencies have been added to the REQUIREMENTS variable ([example][ex-requir]).
• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.