configure: Check version number validity

Here we verify the previously informal invariant that stable release version numbers must have three components, preventing costly failed releases.

Specifically, the check fails in the following scenarios:

• version=9.13 while RELEASE=YES since this would imply a release made from an unstable branch
• version=9.13.0 since unstable versions should only have two components
• version=9.12 since this has the wrong number of version components for a stable branch

Fixes #25390 (closed).