Support QGIS 3.16

[Gustry]

It's a work in progress :

• [x] Check all processing.gui.wrappers_postgis.ConnectionWidgetWrapper
  • [x] Import covadis
  • [x] export covadis
  • [x] load layers
  • [x] load styles
  • [x] configure
  • [x] create
  • [x] upgrade
• [x] Check all processing.gui.wrappers_postgis.SchemaWidgetWrapper, ticket lié #59
  • [x] export covadis
  • [x] import covadis
  • [x] load layers
  • [x] load styles
• [x] Check all processing.gui.wrappers_postgis.TableWidgetWrapper
  • [x] import covadis
• [x] Remove all fetch_data_from_sql_query which is using old DB Manager code
  • [x] upgrade
• [x] Remove all from processing.tools.postgis import uri_from_name
  • [x] export covadis
  • [x] load layers
  • [x] import covadis

[Gustry]

@rldhont The only remaining algorithm broken is the upgrade one, I got issues with it, still related to #91. Strange.

Even if you are running QGIS 3.10, pull and try latest master for your dev.

Commits : d8b70120288aeb08383a4e369ca206d97bc0dbf7 eced0bfe3160b2803e4277df4b97aebcc5ee1de5 a81338d917deb21beb9c026ff59c234b20b3bf3f

[Gustry]

Last commit bfebfee29a45f02bac7e0f4ac479be06127f4412

The ticket can now be closed. I will give it a try again manually.