Don't pin Python patch version

.python-version always matches the minimum supported Python version.
It's main purpose is to catch accidental use of too modern syntax
in scripts and functional tests.

We (currently) don't specify a minimum patch version, so it's not
necessary to do so here. The minor verion is enough.

This also avoids requiring users to keep a potentially unsafe old
patch version installed.

.python-version

@@ -1 +1 @@
-3.10.14
+3.10