Use ICU string for proper countdown via "1 minute"

[NoRi2909]

This PR was motivated by the comment of the Polish localizer who commented on Lokalise:

There should be a way to indicate the correct form of "minuta", depending on the number.
"1 minutę", "2 minuty", "5 minut" are all valid options, for example.

They could then add the line

  =2 {minuty}

to cover that special case, too.

Proposed change

Add ICU syntax to cover "1 minute" as one duration option:

The channel change has been initiated and will complete in {delay} {delay, plural,
  one {minute}
  other {minutes}
}.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (thank you!)
• 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 #
• This PR is related to issue or discussion:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• 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