No, it does not. Git itself is free software, you can download it anywhere and read the source code, which is NOT owned by microsoft. To use git in practice, you need some sort of git server. The main server for FreeBSD's code repository is owned and controlled by the FreeBSD project.
What is true: there is a large git server called "github", which has copies of many software project. Including one copy of the FreeBSD source code. And that server is owned by Microsoft. But you can do git perfectly well without using github.
The more important question is not the technical details. It is: why are you even asking this question? Are you afraid of Microsoft? Microsoft is one of the larger supporters of free and open software, so what would be wrong with using Microsoft servers for source code?