pgAdmin 4 commit: Add support for generated columns in Postgres 12+. Fi

Add support for generated columns in Postgres 12+. Fixes #4334
Ensure columns can be created when they are IDENTITY fields with the CYCLE option enabled. Fixes #4496
Ensure purely numeric comments can be saved on new columns. Fixed #4497

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=2ef3080d0eb2c54e90c32e1cad814062afec9be5
Author: Akshay Joshi <akshay(dot)joshi(at)enterprisedb(dot)com>

Modified Files
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docs/en_US/column_dialog.rst | 60 +++++
docs/en_US/images/column_constraint_generated.png | Bin 0 -> 54461 bytes
docs/en_US/images/column_constraint_identity.png | Bin 0 -> 74201 bytes
docs/en_US/images/column_constraints.png | Bin 0 -> 47511 bytes
docs/en_US/images/column_definition.png | Bin 28807 -> 44189 bytes
docs/en_US/images/column_general.png | Bin 21471 -> 38051 bytes
docs/en_US/images/column_security.png | Bin 26092 -> 43456 bytes
docs/en_US/images/column_variables.png | Bin 23043 -> 41178 bytes
docs/en_US/release_notes_4_12.rst | 3 +
.../databases/schemas/tables/columns/__init__.py | 8 +-
.../schemas/tables/columns/static/js/column.js | 241 ++++++++++++++------
.../tables/columns/tests/test_column_add.py | 124 +++++++----
.../tables/columns/tests/test_column_put.py | 109 +++++----
.../schemas/tables/columns/tests/utils.py | 49 +++++
.../templates/columns/sql/10_plus/create.sql | 8 +-
.../templates/columns/sql/10_plus/properties.sql | 1 +
.../templates/columns/sql/10_plus/update.sql | 13 +-
.../templates/columns/sql/12_plus/create.sql | 46 ++++
.../templates/columns/sql/12_plus/properties.sql | 48 ++++
.../templates/columns/sql/default/create.sql | 2 +-
.../tables/templates/tables/sql/10_plus/create.sql | 6 +-
.../tables/templates/tables/sql/12_plus/create.sql | 7 +-
.../tables/templates/tables/sql/default/create.sql | 2 +-
.../templates/tables/sql/gpdb_5.0_plus/create.sql | 2 +-
.../schemas/tables/tests/test_table_add.py | 245 ++++++++++-----------
.../databases/schemas/tables/tests/utils.py | 78 +++++++
web/pgadmin/static/js/backform.pgadmin.js | 38 +++-
web/pgadmin/static/scss/_bootstrap.overrides.scss | 8 +
28 files changed, 793 insertions(+), 305 deletions(-)