sysutils/azure-agent: reroll distfile

Upstream re-tagged the release to include a merge commit [0] that
fixes merge conflicts. No file or functionality change.

[0] https://github.com/Azure/WALinuxAgent/commit/4d10db69794d9502f47081bbda67ce40152dea25

Approved by: tcberner (mentor), whu (maintainer, implicit)
Differential Revision: https://reviews.freebsd.org/D31173