pgAdmin 4 commit: Ensure the pgAgent job start/end time grid fields syn

Ensure the pgAgent job start/end time grid fields synchronise with the subnode control and validate correctly. Fixes #3073

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=78e2ff4f562e7353cf5452ec4be965aecd6434aa
Author: Murtuza Zabuawala <murtuza(dot)zabuawala(at)enterprisedb(dot)com>

Modified Files
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.../servers/pgagent/schedules/static/js/pga_schedule.js | 8 +++++++-
.../server_groups/servers/pgagent/static/js/pga_job.js | 2 ++
.../servers/pgagent/steps/static/js/pga_jobstep.js | 11 +++++++++++
web/pgadmin/static/js/backform.pgadmin.js | 16 +++++++++++-----
4 files changed, 31 insertions(+), 6 deletions(-)