Update rokuecp to 0.19

[ctalkington]

Proposed change

Allows to pass literal char via remote.send_command. The original white-list in rokuecp prevented such.

https://github.com/ctalkington/python-rokuecp/releases/tag/0.19.0

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)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes Roku Integration - Literal Characters #105776
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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