[New Feature]: Send river levels updates

[nicomontanari]

Describe your proposal

Fetch and check the nearest river sensor levels.

Sensor list: https://allertameteo.regione.emilia-romagna.it/o/api/allerta/get-sensor-values-no-time?variabile=254,0,0/1,-,-,-/B13215
Sensor levels: https://allertameteo.regione.emilia-romagna.it/o/api/allerta/get-time-series/?stazione=3130&variabile=254,0,0/1,-,-,-/B13215

Send messages when:

• the river level goes above the threshold
• the river level goes below the threshold

Technical details

Code of Conduct

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