Trim CW from RGB when not supported in ozw

[firstof9]

Proposed change

Trim the CW from RGB if CW isn't supported.
OZW will not accept 10 value HEX if only 8 values are supported.

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

Additional information

• This PR fixes or closes issue: fixes #n/a
• This PR is related to issue: n/a
• Link to documentation pull request: n/a

Checklist

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[probot-home-assistant]

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

[MartinHjelmare]

Thanks!