Removed current_time attribute from Raincloudy sensors to avoid unnecessary updates by recorder

[tchellomello]

Description:

Removed attribute current_time from Raincloudy sensors to avoid being triggered by recorder component.

One of the Raincloudy attributes was the current_time on the controller to be displayed at HA. This was causing the recorder component to update its status whenever the attributes changed and not only the when it the status changed.

Many thanks to @clboles for reporting this issue. 👍

This PR fixes this and you can find more discussion about it at vanstinator/raincloudy#23

Related issue (if applicable):
See also: vanstinator/raincloudy#23

Pull request in home-assistant.github.io with documentation (if applicable): home-assistant/home-assistant.github.io#<home-assistant.github.io PR number goes here>

Example entry for configuration.yaml (if applicable):

raincloud:
  username: !secret raincloud_username
  password: !secret raincloud_password

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.github.io

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 dependencies are only imported inside functions that use them ([example][ex-import]).
• New dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.
• New files were added to .coveragerc.

If the code does not interact with devices:

• Tests have been added to verify that the new code works.