Prevent automatic dark mode

Add light colorMode to EuiProvider to force light mode theme.

added Accessibility Frontend Priority: high labels

assigned to @remi.bisson

created branch 85-prevent-automatic-dark-mode to address this issue

mentioned in merge request !36 (merged)

mentioned in merge request !37 (merged)

mentioned in commit 07c11ff1

closed with merge request !37 (merged)