Fix FixedRingBuffer.removeAt
Fix FixedRingBuffer.removeAt

There is a problem when removing from the start index

gedaiu/vibe.d,etcimon/vibe.d,etcimon/vibe.d,chalucha/vibe.d,DBankov/vibe.d,Geod24/vibe.d,AndreyMZ/vibe.d,rejectedsoftware/vibe.d