mail/mailpit: Update to 1.9.0

• Pass version number to compiler [1]

Obtained from: https://github.com/axllent/mailpit/blob/b282e6663b559a81e18b1bc94ec7cc7846668c23/.github/workflows/release-build.yml#L48 [1]

(cherry picked from commit 2726d70eb4ae66c09cfe9947043bcb1d70014d86)