Optimize bloated ca-bundle into service specific bundles

[tripflex]

Related to #3 and mongoose-os-libs/gcp#6 (comment)

The full ca-bundle has grown over time, ultimately resulting in a bloated library that is included even when certain certificates are not needed. And as MOS continues to grow, this will become more and more of an issue.

As mentioned by @rojer mongoose-os-libs/gcp#6 (comment)

ultimately, i think, the bundle should be unbundled and we should have each library add its own ca file and mos (mbedtls, really) to be able to check them all. e.g., set ca_cert="*ca.pem", so it will match gcp.ca.pe, aws.ca.pem and make adding your own ca files easy - just call it something.ca.pem and it will match. but it requires change to mbedtls, somewhat non-trivial.
so, for now i think we'll just have to add another cert to the bundle.

[fabiohmantelli]

This has been an issue for me. In my case, when I add the aws library to my mos.yml file, on build process I don't have enough space in my fs, and the 31 kb ca.pem file seems to be the problem. I get the following error, while trying to write another file to the fs, after I have added the ca.pem file:

SPIFFS_write failed: -10001 *** Out of space, tried to write 2836 bytes ***

[fabiohmantelli]

Same problem over here. Hope this gets worked out

This has been an issue for me. In my case, when I add the aws library to my mos.yml file, on build process I don't have enough space in my fs, and the 31 kb ca.pem file seems to be the problem. I get the following error, while trying to write another file to the fs, after I have added the ca.pem file:

SPIFFS_write failed: -10001 *** Out of space, tried to write 2836 bytes ***