docs: update releasing.md

- the file itself does not need to be modified
- I'll update the release issue template if it needs to be modified

#closes 1080

docs/dev/howto/releasing.md

@@ -1,7 +1,3 @@
-```{warning}
-FIXME(arthur): to update with the new workflow
-```
-
 # Creating A Release On GitHub
 
 ## Release Candidate cycle