Update various social links.

Author: KelSolaar

README.rst

@@ -53,7 +53,8 @@ The *Colour Developers* can be reached via different means:
 - `Email <mailto:colour-developers@colour-science.org>`__
 - `Facebook <https://www.facebook.com/python.colour.science>`__
 - `Gitter <https://gitter.im/colour-science/colour>`__
-- `Twitter <https://twitter.com/colour_science>`__
+- `X <https://x.com/colour_science>`__
+- `Bluesky <https://bsky.app/profile/colour-science.bsky.social>`__
 
 About
 -----