Add mdbook team

[GuillaumeGomez]

Follow-up of the zulip discussion.

Now pinging all dev-tools teams (in no particular order) so everyone is aware of this new team joining dev-tools. :)

cc @rust-lang/devtools @rust-lang/clippy @rust-lang/clippy-contributors @rust-lang/cargo @rust-lang/crates-io @rust-lang/docs-rs @rust-lang/rustdoc @rust-lang/rustfmt @rust-lang/rustfmt-contributors @rust-lang/rustup @rust-lang/testing-devex @rust-lang/wg-bindgen

[github-actions]

Dry-run check results

[WARN  rust_team::sync] sync-team is running in dry mode, no changes will be applied.
[INFO  rust_team::sync] synchronizing crates-io
[INFO  rust_team::sync] synchronizing github
[INFO  rust_team::sync] 💻 Team Diffs:
    ➕ Creating team:
      Org: rust-lang
      Name: mdbook
      Description: Managed by the rust-lang/team repository.
      Privacy: closed
      Members:
        GuillaumeGomez: member
        camelid: member
        notriddle: member
    📝 Editing team 'rust-embedded/triage':
      Adding member 'jessebraham' with member role
    📝 Editing team 'rust-embedded/risc-v':
      Adding member 'jessebraham' with member role
    💻 Repo Diffs:
    📝 Editing repo 'rust-lang/mdBook':
      Permission Changes:
        Giving team 'mdbook' write permission
        Removing team 'devtools''s write permission 
        Removing user 'Dylan-DPC''s write permission 
      Rulesets:
          Updating 'master'
            Required approvals: 0 => 1
      Environments:
        ❌ Delete: copilot