pgAdmin 4 commit: Fixes #1262 - Do not allow to delete the default serv

Fixes #1262 - Do not allow to delete the default server group.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=afcb62cfd67ec6c7f9a70a074afb071f5fc50f27
Author: Murtuza Zabuawala 

Modified Files
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web/pgadmin/browser/server_groups/__init__.py      | 29 ++++++++++++++--------
.../templates/server_groups/server_groups.js       |  6 ++---
2 files changed, 21 insertions(+), 14 deletions(-)