Properly resolve a user's TSO prefix

For the odd shops like ours where a TSO prefix is not the user's ID, this can cause a lot of ZOAU commands/python invocations to fail. ZOAU tries to allocate temporary work datasets under the user's "prefix", but it seems to just grab the user's ID instead of the actual tso prefix.

Example (using ZOAU hlq command to get the "prefix", then issuing tso command profile to get the actual prefix):

X261281:/ZAZ0/tmp: >hlq

X261281

X261281:/ZAZ0/tmp: >tsocmd profile

profile

CHAR(0) LINE(0) PROMPT INTERCOM NOPAUSE NOMSGID NOMODE NOWTPMSG NORECOVER PREFIX(BX87DE) PLANGUAGE(ENU) SLANGUAGE(ENU) VA

RSTORAGE(LOW)

X261281:/ZAZ0/tmp: >

This becomes a fatal issue if the user does not have an active alias (or if the user has no authority to create datasets that are under said HLQ).