pgAdmin 4 commit: pgAgent fixes:

pgAgent fixes:

"malformed array literal error when updating pgagent job". Fixes #4428
"Error when updating connection string in pgagent Jobs.". Fixes #4448
When user create a schedule using Create->Schedule dialog browser tree is not showing newly created node.
Properties tab showing same properties for all the created schedule.
Added validation in "pga_jobstep.js", throws error on browser when we modify step from the pgagent dialog and select
thesame node. 

Branch
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electron2

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=9312b34c721baafe6c286f9c526d23a93e90908e
Author: Akshay Joshi <akshay.joshi@enterprisedb.com>

Modified Files
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docs/en_US/release_notes_4_11.rst                  |  2 +
.../server_groups/servers/pgagent/__init__.py      | 52 ++++++++++++++
.../servers/pgagent/schedules/__init__.py          | 56 ++-------------
.../pgagent/schedules/static/js/pga_schedule.js    |  3 +-
.../servers/pgagent/steps/static/js/pga_jobstep.js | 11 +--
.../templates/pga_job/sql/pre3.4/update.sql        | 12 +++-
.../templates/pga_schedule/sql/pre3.4/create.sql   |  4 +-
.../pga_schedule/sql/pre3.4/properties.sql         |  2 +-
.../servers/pgagent/tests/test_pgagent_add.py      |  3 +-
.../servers/pgagent/tests/test_pgagent_put.py      | 79 ++++++++++++++++++++--
.../browser/server_groups/servers/pgagent/utils.py | 46 +++++++++++++
11 files changed, 204 insertions(+), 66 deletions(-)