HTTPS Client is not compliant with HTTP 1.1

[gregjesl]

We've been using your example with great success for a while but have recently run into an issue with file downloads. After digging in to the issue, it turns out the https_client used in this example is not compliant with HTTP 1.1.

Per the HTTP 1.1 spec:

All HTTP/1.1 applications MUST be able to receive and decode the "chunked" transfer-coding, and MUST ignore chunk-extension extensions they do not understand.

When a response is chunked, no Content-Length header is sent (see here for more details); however, the HTTPS client will fail if the Content-Length header is not set in the response: https://github.com/classycodeoss/esp32-ota-https/blob/88c001bf8156b77b83b20ffec6784455b1facb8f/main/https_client.c#L215-L225