Mass edit to remove redundant suffixes from citybike station names.

Some reasoning for "new" format:
*follows "official" station names
*follows "Map what's on the ground"-practice
*follows format of similar tags (e.g. bus stops).

To help search engines, 'citybike station' is still mentioned in alt_names.

Originally suggested by HSL. Related discussion: https://forum.openstreetmap.org/viewtopic.php?id=72745