Move inactive t-triage members to alumni

[Kobzol]

This PR combines:

• Move johncsimon to alumni #2609
• Move shard77 to alumni #2608
• Move tranquillity-codes to alumni #2603
• Move Muirrum to alumni #2598

Together to avoid multiple rebases.

[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:
    📝 Editing team 'rust-lang/all':
      Deleting member 'shard77'
      Deleting member 'Muirrum'
      Deleting member 'JohnCSimon'
      Deleting member 'tranquillity-codes'
    📝 Editing team 'rust-lang/triage':
      Deleting member 'Muirrum'
      Deleting member 'JohnCSimon'
      Deleting member 'shard77'
      Deleting member 'tranquillity-codes'
    💻 Org membership Diffs:
    ❌ Removing the following members from `rust-lang`:
      - JohnCSimon
      - Muirrum
      - shard77
      - tranquillity-codes