Revert converter function for Time metdata

Turns out there was a formatting issue in mongodb which made it not work,
but which is now resolved.
1 job for master in 36 seconds (queued for 2 seconds)
Status Name Job ID Coverage
  Test
failed test #6083

00:00:36

 
Name Stage Failure
failed
test Test
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TOTAL 381 365 4%

=========================== short test summary info ============================
ERROR sdc/tests/test_client.py
!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!
========================= 1 warning, 1 error in 2.14s ==========================
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1