Resolve "Issue weight empty state in sidebar doesn't match other blocks"

Closes #2010

See merge request !1512

Remove N+1 queries for Groups::AnalyticsController

Closes gitlab-ce#22940 and #1886

See merge request !1514

Closes gitlab-org/gitlab-ce#22940, #1886

Allow downgrade when no users were added in previous period

See merge request !1490

Currently a customer can't downgrade because validations will fail given
the historical max will be greater than the current active users. If
customer hasn't added more users in the previous period we should
compare against the current active users instead.

Change full colors to a more harmonious palette

See merge request !1504

Show loading icon when changing filter in add issues modal EE port

See merge request !1505

# Conflicts:
#	app/assets/stylesheets/framework/variables.scss

Closes #29615

Fix dead docs link

See merge request !1492

Lightly refactor js files related to file template selectors.

See merge request !1496

Fixes issue not adding with milestone on board with associated milestone

Closes #1934 and gitlab-ce#29612

See merge request !1445

CE upstream: Thursday

See merge request !1497