Revert "Require CMake 3.21 (#16783)"
Revert "Require CMake 3.21 (#16783)"

This reverts commit fe8be75d4f1bc2a4abf04f48564472bd4e1bd4cf.

arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,arangodb/arangodb,arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb