mirage/mirage-skeleton: PR #420: Bump ocamlformat version

@01b3663

Stages:

• ❌ x86_64-debian-13-4.14 (2m24s)
• ❌ arm64-debian-13-4.14 (1s)
• ❌ x86_64-debian-13-5.3 (1m43s)
• ❌ arm64-debian-13-5.3 (8s)
• ❌ x86_64-debian-13-5.4 (2m55s)
• ❌ arm64-debian-13-5.4 (25s)

History:

• 27/03/2026 17:37 ❌ @01b3663 (9m23s)