Adding Buderus KM271-WiFi to esphome devices

[the78mole]

Brief description of the changes

Added a new device I created for ESPhome.

Type of changes

• [X] New device
• [ ] Update existing device
• [ ] Removing a device
• [ ] General cleanup
• [ ] Other

Checklist:

• [X] There are no passwords or secrets references in any examples. The only exceptions are !secret wifi_ssid and !secret wifi_password.
• [X] The wifi or ethernet block has no static / manual ip address specified.
• [X] The first configuration provided should be hardware definitions only. A more involved example can be provided in a separate configuration block.

[netlify[bot]]

✅ Deploy Preview for esphome-devices ready!

Name	Link
🔨 Latest commit	f5920d189325e307557b6088122bd55dea589e94
🔍 Latest deploy log	https://app.netlify.com/sites/esphome-devices/deploys/6787be55a90e940008c1bb37
😎 Deploy Preview	https://deploy-preview-987--esphome-devices.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.
Lighthouse	1 paths audited Performance: 96 (🟢 up 17 from production) Accessibility: 86 (no change from production) Best Practices: 100 (no change from production) SEO: 89 (no change from production) PWA: 70 (no change from production) View the detailed breakdown and full score reports

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[esphome[bot]]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks :+1:

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