Add Hong Kong Observatory (#1993)

README.md

@@ -1227,6 +1227,7 @@ API | Description | Auth | HTTPS | CORS |
 | [AviationWeather](https://www.aviationweather.gov/dataserver) | NOAA aviation weather forecasts and observations | No | Yes | Unknown |
 | [ColorfulClouds](https://open.caiyunapp.com/ColorfulClouds_Weather_API) | Weather | `apiKey` | Yes | Yes |
 | [Foreca](https://developer.foreca.com) | Weather | `OAuth` | Yes | Unknown |
+| [Hong Kong Obervatory](https://www.hko.gov.hk/en/abouthko/opendata_intro.htm) | Provide weather information, earthquake information, and climate data | No | Yes | Unknown |
 | [MetaWeather](https://www.metaweather.com/api/) | Weather | No | Yes | No |
 | [Meteorologisk Institutt](https://api.met.no/weatherapi/documentation) | Weather and climate data | `User-Agent` | Yes | Unknown |
 | [NOAA Climate Data](https://www.ncdc.noaa.gov/cdo-web/) | Weather and climate data | `apiKey` | Yes | Unknown |