[pgadmin-hackers] pgAdmin 4 commit: Fix the issue where Import/Export was failing inlinu

Fix the issue where Import/Export was failing in linux runtime. Fixes #2166

Issue:
Changes done by Ashesh in pgAdmin4.py file for setting up PYTHONHOME variable to sys.prefix was applicable only for
windowsonly. 

Additionally I have also added exception handling for file provided by user for Backup/Restore/Import/Export.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=bc63652811f7fdc1080102bf70f0ecc7aae496d6
Author: Murtuza Zabuawala <murtuza.zabuawala@enterprisedb.com>

Modified Files
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web/pgAdmin4.py                             |  4 +++-
web/pgadmin/misc/bgprocess/processes.py     |  2 +-
web/pgadmin/tools/backup/__init__.py        | 10 ++++++++--
web/pgadmin/tools/import_export/__init__.py |  6 +++++-
web/pgadmin/tools/restore/__init__.py       |  5 ++++-
5 files changed, 21 insertions(+), 6 deletions(-)