databases/mongodb70: 7.0.39

Announcement:
https://www.mongodb.com/community/forums/t/mongodb-7-0-39-is-released/341747?u=r_k

Changelog:
https://www.mongodb.com/docs/manual/release-notes/7.0/#7.0.39---july-22--2026

Security: a whole list of CVEs in the changelog