/usr/lib/linux/4.18.0-1013-azure/compiler is in linux-buildinfo-4.18.0-1013-azure 4.18.0-1013.13~18.04.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1
GCC: (Ubuntu 7.3.0-16ubuntu3) 7.3.0