Strip trailing slashes to avoid 404 from Home Assistant's API endpoint

[lassebm]

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Description

Strip trailing slashes to avoid 404 from Home Assistant's API endpoint.

Type of change

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• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

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[ThomDietrich]

Hey @lassebm,
just out of interest. How did you define your Home Assistant check? Mine is configured this way and no fix via a PR was needed. Do you have a better check I might want to adapt?

[lassebm]

@ThomDietrich If you had a trailing slash in the URL before the PR, HA would 404 due to double slashes in the constructed URL.

[ThomDietrich]

ah ^^ okay that makes sense. Thanks for your PR :)