Values:
RESOLUTION_STATUS_UNSPECIFIED (0):
Status is unknown. When left unspecified in
requests, it is treated like OPEN.
OPEN (1):
The error group is not being addressed. This
is the default for new groups. It is also used
for errors re-occurring after marked RESOLVED.
ACKNOWLEDGED (2):
Error Group manually acknowledged, it can
have an issue link attached.
RESOLVED (3):
Error Group manually resolved, more events
for this group are not expected to occur.
MUTED (4):
The error group is muted and excluded by
default on group stats requests.
