fix: Weather and TLS

[schw4rzlicht]

Hello there,

I noticed some issues with the weather code / TLS. There was an undefined variable that I am fixing in this PR:

https://github.com/schw4rzlicht/ikea-led-obegraensad/blob/670b0e7191ce6a9dbbc8048b12e74ad94ae4145b/src/mode/weather.cpp#L50

Additionally, following was changed to fix an issue with the weather mode (wttr.in is only available via HTTPS now):

• data/cert/cacert-2023-08-22.pem: the latest certificate store from Mozilla ^1
• data/cert/dst_root_ca_x3.pem: the DST Root CA X3 certificate from LetsEncrypt ^2 which is needed, see
  • https://github.com/espressif/arduino-esp32/issues/6060
  • https://github.com/espressif/arduino-esp32/issues/8626
• data/cert/x509_crt_bundle.bin: the bundled certificates ready for upload to the esp
• gen_crt_bundle.py: bundle script that creates data/cert/x509_crt_bundle.bin[^4][^5]
• include/mode/weather.h: changed lastUpdate to nextUpdate to facilitate quicker retries on failure
• platformio.ini: added board_build.embed_files configuration to upload the cert bundle
• src/mode/weather.cpp:
  • using WifiClientSecure now to support TLS
  • quicker retries on failure
  • error output when HTTP(S) GET fails
• src/webgui.cpp: not even sure why this was updated...

The certs will need regular updates, maybe use Github actions for that?

Thanks for your feedback!

[^2]: expired, see https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/

[^5]: see explanation here