Externals Update, master branch (2022.01.11.)

Updated all projects to atlasexternals-2.0.124. The changes wrt. atlasexternals-2.0.123 are the following (atlasexternals@2.0.123...2.0.124):

• Silenced the messages from OpenMP while looking for the BLAS library, fixing AGENE-2118 (see https://gitlab.kitware.com/cmake/cmake/-/issues/23000 for some background information);
• Made it possible to declare multiple environment variables in atlas_add_test(...) (thanks to @goetz for reporting the problem);
• Upgraded Gdb to version 11.1 (thanks to @ssnyder);
  • Note that this is the same as what @elmsheus implemented in !49520 (merged). The two MRs do not clash with each other. However once we updated to atlasexternals-2.0.124 (with this MR), we should reverse !49520 (merged). (Sorry Johannes, I ended up making the new tag more quickly than I thought yesterday that I would...)
• Added the location of the sqlite executable to the PATH environment variable (thanks to @rbianchi);
• Removed cppcheck from AthenaExternals (see ATLINFR-2654 for some of the details).

It's probably not needed, but just to be safe (and since these changes are not super urgent), let's use full-build. 😉