Add missing config flow translation key for Nest

[frenck]

Proposed change

The OAuth2 configuration flow for the new Nest DSM is missing a translation key, causing a user with no available URLs on their system to get an empty abort dialog.

⚠️ This PR needs to go into 0.117 and this requires translation updates on the rc branch.

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

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[probot-home-assistant]

Hey there @awarecan, @allenporter, mind taking a look at this pull request as its been labeled with an integration (nest) you are listed as a codeowner for? Thanks!
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