Integrate more tools in CI

[ROMemories]

List of tools/functionalities we may want to integrate now in CI:

• Check intra-doc links by building the docs of riot-rs-embassy with -D warnings ci(rustdoc): check rustdoc generation #113
• Only trigger the mdbook workflow when the book/ directory was changed ci(book): run the mdbook workflow only when its directory has changed #111
• Integrate cargo-sort in CI ci(cargo-sort): check formatting and item order of Cargo.toml files #116
• Check rustfmt formatting ci: add rustfmt check #118
• Check intra-doc links by building the docs of riot-rs with -D warnings ci(docs): check doc generation for the riot-rs crate #132
• Run crate tests for major crates Run cargo test in CI #110 ci: run crate tests #139
• Make clippy check the whole workspace
• Run crate tests for the whole workspace

List of tools/functionalities we may want to integrate later in CI:

• cargo-semver-checks and/or cargo-public-api
• miri
• cargo-udeps
• cargo-deny, GitHub Action
• Monitor binary size and static allocations of examples