pgAdmin 4 commit: Improvise the PostgreSQL driver to fetch the status m

Improvise the PostgreSQL driver to fetch the status message.

At the moment, we will only allow to fetch status messages from the
asynchronous connection only, later - we may implement to fetch the
status message from the normal connection too.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=e585ddbdafc896c7e494fd65b01d5c586d3db0cd
Author: Neel Patel <neel.patel@enterprisedb.com>

Modified Files
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web/pgadmin/utils/driver/abstract.py          |  4 ++++
web/pgadmin/utils/driver/psycopg2/__init__.py | 32 +++++++++++++++++++++------
2 files changed, 29 insertions(+), 7 deletions(-)