Mention the mock tempate for RHEL and the Buildsystem building group …

…for Fedora.

Co-authored-by: Scott Logan <[email protected]>

ros-build-essential/README.md

@@ -8,11 +8,10 @@ It should include the base toolchain for any operating system (such as `build-es
 This variant is meant primarily for internal use by the ROS Infrastructure team to set up the environment in which packages will be built on the ROS build farm.
 Since this package is used by the more user-facing ros-dev-tools variant as well, it can be useful to define the variant for platforms that are not currently enabled, or potentially even supported, by the build farm infrastructure.
 When selecting packages to include in this variant, the platform's own build toolchain, including any utilities used in the package creation process, should be used as a starting point.
-For example the `build-essential` package in Debian, `base-devel` in Arch Linux, or the `Development Tools` group in RHEL.
+For example the `build-essential` package in Debian, `base-devel` in Arch Linux, the [mock template setup](https://github.com/rpm-software-management/mock/blob/0e7e8db8489563cbd6a21378860f45828c25a99b/mock-core-configs/etc/mock/templates/almalinux-8.tpl#L1) for RHEL, or the `Buldsystem building group` in Fedora.
 
 If the default build toolchain for a distribution does not include GNU Make and a C++ compiler, those should be included as well.
 
-
 ### Additional packages included in this variant
 
 * cmake