1.19.0 MR
Docs updates only.
Gitlab Synker changes are only required for this release and won't be cherrypicked back (https://repo1.dso.mil/platform-one/big-bang/bigbang/-/commit/98fc921701f1f719e3bbb14873cc64e3bd25c67a).
All other changes are in master.
Edited by Micah Nagel