Merge branch '8.x-1.x' into 91-decentralisation

# Conflicts:
#	tests/src/fixtures/base_theme/base_theme.ui_patterns.yml
#	tests/src/fixtures/module/module.ui_patterns.yml
#	tests/src/fixtures/theme/pattern/pattern.ui_patterns.yml
#	tests/src/fixtures/theme/theme.ui_patterns.yml