MDL-47260 core_grades: Prevent notices when setting up other aggregation method

This partially reverts:

- 4927c3ff (MDL-47011)
- 6484d460 (MDL-47055)

Part of: MDL-46576
MDL-47056 core_grades: Prevent items being displayed as 'Error'

Before this patch we would be marking some items as 'needsupdate'
during an update. Leaving them aside and not effectively updating
them.

Part of: MDL-46576
MDL-46966 grades: change aggregation method default

Also fix affected behat tests
MDL-47146 grades: merge simple and full view in setup

AMOS BEGIN
 CPY [categoriesanditems,core_grades],[setup,core_grades]
AMOS END
MDL-47146 grades: remove advanced mode in setup
hide select column if no categories
action buttons
Fix navbar
temp