Improve certificate related documentation

[didier-wenzek]

Proposed changes

• Add overview
• Improve section related to self-signed certificate
• Add howto use CA-signed certificate
• Improve section related to cloud certificate
• Polish doc related to MQTT TLS + auth settings
• Add doc for HTTP TLS + auth settings

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (general improvements like code refactoring that doesn't explicitly fix a bug or add any new functionality)
• Documentation Update (if none of the other choices apply)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Paste Link to the issue

• Cleanup documentation for 1.0.0 #2551
• Use CA signed certificates #1505

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA (in all commits with git commit -s)
• I ran cargo fmt as mentioned in CODING_GUIDELINES
• I used cargo clippy as mentioned in CODING_GUIDELINES
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (5eb1219) 75.8% compared to head (5761e2b) 75.8%.

❗ Current head 5761e2b differs from pull request most recent head f79b243. Consider uploading reports for the commit f79b243 to get more accurate results

Additional details and impacted files

Files	Coverage Δ
.../tedge_config/src/tedge_config_cli/tedge_config.rs	81.1% <100.0%> (ø)

... and 7 files with indirect coverage changes

[reubenmiller]

I've added a few minor comments.

Currently most of the filenames no longer match the scope of the doc, .e.g the file add_self_signed_trusted.md, has a title of Cloud Authentication, and registration.md has a title of Self-signed Device Certificate.

We should fix the filenames so that the slugs (e.g. doc url) and the filenames are semi-related so it is easier for developers to find and maintain the docs.

[jarhodes314]

I wonder whether it's worth clarifying how this works in case people wish to use an IP address to connect instead. Firstly, it's not unlikely that people will want to connect by something other than localhost or the hostname of the machine, Secondly, when using an IP it's easy to fall into the trap of using e.g. DNS:192.168.0.25 where this should actually be IP:192.168.0.25 (and if you make mistakes here, you'll get next to no help in the error message to enlighten you as to what is wrong).

[didier-wenzek]

Added a note

[didier-wenzek]

Currently most of the filenames no longer match the scope of the doc, .e.g the file add_self_signed_trusted.md, has a title of Cloud Authentication, and registration.md has a title of Self-signed Device Certificate.

We should fix the filenames so that the slugs (e.g. doc url) and the filenames are semi-related so it is easier for developers to find and maintain the docs.

This has been fixed with 5ae1828

[reubenmiller]

Approved. My comments have now been addressed.

[github-actions]

Robot Results

✅ Passed	❌ Failed	⏭️ Skipped	Total	Pass %	⏱️ Duration
380	0	3	380	100	54m11.187s