Make use of "fetch_json" for other asynchronous functions

[LAMaglan]

async def fetch_json(url: str) -> dict:
    async with httpx.AsyncClient() as client:
        response = await client.get(url)
        if response.status_code == 200:
            return response.json()
        else:
            raise HTTPException(
                status_code=response.status_code, detail="Resource not found at URL: " + url
            )

See how it is used in get_locations