Use backticks around TryFrom and FromStr in the output comments

[proski]

Missing backticks trigger the pedantic doc_markdown lint in clippy.

[ahl]

Thanks! How did you encounter this? Would it make sense to enable certain clippy lints in testing to ensure that we don't backslide?

[proski]

I enabled all clippy categories apart from "nursery" in Cargo.toml:

[lints.clippy]
correctness = { level = "deny", priority = -1 }
suspicious = { level = "warn", priority = -1 }
complexity = { level = "warn", priority = -1 }
perf = { level = "warn", priority = -1 }
style = { level = "warn", priority = -1 }
pedantic = { level = "warn", priority = -1 }
cargo = { level = "warn", priority = -1 }

I was using import_types! originally. Clippy doesn't warn about results of macro expansion. Then I switched to build.rs as I wanted to have more control. Clippy warns about included files. Also, there is no way to suppress lints for macro expansion only, and I didn't want to suppress them for the whole file that deals with the loaded JSON file. So I added some regex replacements to build.rs.

All warnings are from clippy::doc_markdown (part of clippy::pedantic). One warning is about "TryFrom or FromStr". The other is for the first comment line above the struct definition, e.g. ///SenderConfig in this example:

///SenderConfig
///
/// <details><summary>JSON schema</summary>
///
/// ```json
///{
///  "title": "SenderConfig",

I was short on time when I made this PR, but now I see how to fix it. The comment comes from make_doc and there is a way to work it around by adding a description. But if there is no description, the name should be in backticks.

The test would be to run cargo clippy with all lints on the generated code.

On a related note, I'm surprised that the CI didn't run on my pull requests.