pgAdmin 4 commit: Give a more useful error message if attempting to dro

Give a more useful error message if attempting to drop an object that doesn't exist. Fixes #1154

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=166d42953ced62f527f8d1e512fd519026ac895c
Author: Harshal Dhumal <harshal.dhumal@enterprisedb.com>

Modified Files
--------------
.../server_groups/servers/databases/__init__.py       |  3 +++
.../server_groups/servers/databases/casts/__init__.py | 11 +++++++++++
.../servers/databases/event_triggers/__init__.py      | 11 +++++++++++
.../servers/databases/extensions/__init__.py          | 12 ++++++++++++
.../databases/foreign_data_wrappers/__init__.py       | 11 +++++++++++
.../foreign_data_wrappers/foreign_servers/__init__.py | 12 ++++++++++++
.../foreign_servers/user_mapping/__init__.py          | 19 +++++++++++++++++++
.../servers/databases/schemas/__init__.py             | 12 ++++++++++++
.../servers/databases/schemas/collations/__init__.py  | 11 +++++++++++
.../servers/databases/schemas/domains/__init__.py     | 11 +++++++++++
.../schemas/domains/domain_constraints/__init__.py    | 11 +++++++++++
.../databases/schemas/foreign_tables/__init__.py      | 11 +++++++++++
.../databases/schemas/fts_configurations/__init__.py  | 14 ++++++++++----
.../databases/schemas/fts_dictionaries/__init__.py    | 14 ++++++++++----
.../servers/databases/schemas/fts_parser/__init__.py  | 12 ++++++++++--
.../databases/schemas/fts_templates/__init__.py       | 11 +++++++++++
.../servers/databases/schemas/functions/__init__.py   | 11 +++++++++++
.../servers/databases/schemas/sequences/__init__.py   | 11 +++++++++++
.../servers/databases/schemas/tables/__init__.py      | 12 ++++++++++++
.../databases/schemas/tables/column/__init__.py       | 11 +++++++++++
.../tables/constraints/check_constraint/__init__.py   | 11 +++++++++++
.../constraints/exclusion_constraint/__init__.py      | 11 +++++++++++
.../tables/constraints/foreign_key/__init__.py        | 11 +++++++++++
.../tables/constraints/index_constraint/__init__.py   | 11 +++++++++++
.../databases/schemas/tables/indexes/__init__.py      | 11 +++++++++++
.../databases/schemas/tables/rules/__init__.py        | 12 ++++++++++++
.../databases/schemas/tables/triggers/__init__.py     | 11 +++++++++++
.../servers/databases/schemas/types/__init__.py       | 11 +++++++++++
.../servers/databases/schemas/views/__init__.py       | 11 +++++++++++
.../server_groups/servers/resource_groups/__init__.py | 12 ++++++++++++
.../server_groups/servers/tablespaces/__init__.py     | 12 +++++++++---
31 files changed, 342 insertions(+), 13 deletions(-)