Merge pull request #234 from tnguyen-ornl/tnguyen/fix-missing-headers-gcc11

Added <optional> header include
3 jobs for master in 64 minutes and 30 seconds (queued for 5 seconds)
Name Stage Failure
docker run_macosx_catalina_bottles Deploy

real 10m31.545s
user 0m0.235s
sys 1m3.994s
++ docker run -d -it --device /dev/kvm -p 50922:10022 -v /home/gitlab-runner/builds/pqx9Es-r/0/qci/qcor/mac_hdd_ng_auto.img:/image sickcodes/docker-osx:naked
docker: Error response from daemon: driver failed programming external connectivity on endpoint nifty_dhawan (7e9bc232d5f23607eca7c933d590fc5c408b8c901233190b8594d186aa9e6f93): Bind for failed: port is already allocated.
+ id=002d16cbb7a43507f6635abfd93a8cc5d6ef2bfe37a13846ca2de620ebf97ee6
Cleaning up project directory and file based variables
ERROR: Job failed: exit status 1