Add pymodbus exception handling and isolate pymodbus to class modbusHub

[janiversen]

Breaking change

Proposed change

Add pymodbus exception handling directly in the class modbusHub in order to isolate the pymodbus library.

This has 2 consequences:

• platforms using modbusHub do not receive exceptions, but may receive None
• Testing of the pymodbus library are limited to class pymodbus (see PR Test pymodbus #49053).

The old code could deliver wrong data during startup, especially if the device were slow to connect, this
Should now be history.

STATE_UNAVIALABLE was not set in all platforms, so sometimes there were not data, but HA was not made aware
That the data was invalid.

There is a major rewrite of the test_modbus.py module, submitted in the next PR, to thoroughly test exceptions/writes etc.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example entry for configuration.yaml:

# Example configuration.yaml

Additional information

• This PR fixes or closes issue: fixes #
  fixes After restart of Home Assistant Modbus registers sometimes show wrong values until new restart of HA #40936
  fixes Modbus: write_register multi #45079
  fixes Modbus errors after upgrading to HA v2021.4.0 and new config style #49011
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

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

• Documentation added/updated for www.home-assistant.io

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

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• Untested files have been added to .coveragerc.

The integration reached or maintains the following Integration Quality Scale:

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To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[probot-home-assistant]

Hey there @adamchengtkc, @vzahradnik, mind taking a look at this pull request as its been labeled with an integration (modbus) you are listed as a codeowner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[janiversen]

Update to newest dev which includes changes to modbus.