pgAdmin 4 commit: Do not reset the driver registry when the 'load_drive

Do not reset the driver registry when the 'load_driver' method of
DriverRegistry is executed second time.

Also, initialize the driver before registering different blueprints,
which uses those driver inside them.

Thanks Khushboo for reporting the issue.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=26e9ceaf48a1fb66c1e62882a9f8c1482f0dc7c8

Modified Files
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web/pgadmin/__init__.py              | 6 +++---
web/pgadmin/utils/driver/registry.py | 6 ++++--
2 files changed, 7 insertions(+), 5 deletions(-)