add OPSI (Slovenia Open Data) (#2727)

README.md

@@ -945,6 +945,7 @@ API | Description | Auth | HTTPS | CORS |
 | [Open Government, Saudi Arabia](https://data.gov.sa) | Saudi Arabia Government Open Data | No | Yes | Unknown |
 | [Open Government, Singapore](https://data.gov.sg/) | Singapore Government Open Data | No | Yes | Unknown |
 | [Open Government, Slovakia](https://data.gov.sk/en/) | Slovakia Government Open Data | No | Yes | Unknown |
+| [Open Government, Slovenia](https://podatki.gov.si/) | Slovenia Government Open Data | No | Yes | No |
 | [Open Government, South Australian Government](https://data.sa.gov.au/) | South Australian Government Open Data | No | Yes | Unknown |
 | [Open Government, Spain](https://datos.gob.es/en) | Spain Government Open Data | No | Yes | Unknown |
 | [Open Government, Sweden](https://www.dataportal.se/en/dataservice/91_29789/api-for-the-statistical-database) | Sweden Government Open Data | No | Yes | Unknown |