Docs: update "making releases" doc based on 6.7/6.7.1 retrospective

After our 6.7/6.7.1 [retrospective](https://docs.google.com/document/d/18PA2N9Sf6604YBD1mtU1tA7WOkWCz5M93rqus2j1x-k/edit?tab=t.oc8iau8l8p9b#heading=h.8v03j9o4y744) we decided to tweak our "making releases" docs a bit:

<img width="879" height="337" alt="Image" src="https://github.com/user-attachments/assets/addc156d-2156-42f0-a9ea-0516b3f736b7" />