pgAdmin 4 commit: Standardise the error handling for parsing of JSON re

Standardise the error handling for parsing of JSON response messages from the server. Fixes #3238

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=893737588509425849b0fde3068d34f4950e9ce2

Modified Files
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docs/en_US/release_notes_3_1.rst | 7 +-
.../servers/databases/casts/static/js/cast.js | 11 +--
.../schemas/synonyms/static/js/synonym.js | 11 +--
.../check_constraint/static/js/check_constraint.js | 11 +--
.../foreign_key/static/js/foreign_key.js | 11 +--
.../tables/partitions/static/js/partition.js | 49 +++----------
.../databases/schemas/tables/static/js/table.js | 49 +++----------
.../schemas/tables/triggers/static/js/trigger.js | 22 ++----
.../databases/schemas/views/static/js/mview.js | 5 +-
.../servers/databases/static/js/database.js | 11 +--
.../servers/pgagent/static/js/pga_job.js | 20 +-----
.../server_groups/servers/static/js/server.js | 77 ++++-----------------
.../servers/tablespaces/static/js/tablespace.js | 11 +--
web/pgadmin/browser/static/js/browser.js | 18 ++---
web/pgadmin/dashboard/static/js/dashboard.js | 11 +--
web/pgadmin/static/js/alertify.pgadmin.defaults.js | 39 +++++++++++
.../javascript/alerts/alertify_wrapper_spec.js | 80 ++++++++++++++++++++++
17 files changed, 183 insertions(+), 260 deletions(-)