[Enhancement] The colors of the observation graph change upon changing the year range

[SanderDevisscher]

Feature title

Species information > observations

Description

The graph below the map changes color when you change the year range.

todo add screenshots

[mvarewyck]

@SanderDevisscher You mean the legend colors should be fixed? Example below for Abies Alba: Flanders switches from green to blue

[SanderDevisscher]

exactly