I have refactored the test harness for the blueprints http client to not extent the sail proxy test suite mechanism.
I have done a preliminary root cause analysis
BLZG-1174. The underlying issue appears to be the cached of the GRS btree reference on the GlobalRowStoreHelper object tightly held by the Journal is not being updated when the CreateKBTask creates a GSR within the scope of an IsolatedActionJournal.
A similar issue is documented in the constructor of the IsolatedActionJournal.
We probably need to refactor the cache mechanisms for the GSR to support isolation by AbstractTask.
Note: This does not imply that the blueprints http client is broken when group commit is enabled. It is probably fine. This problem is causing test harness failures.