Python: Update .expected to support Python 3.12

You might wonder why the number of lines changed, but it's due to `tty`
module receiving its' first update since 2001, so the actual number of
lines DID change :phew:

https://github.com/python/cpython/commits/3.12/Lib/tty.py

Since there is now a difference between Python 2 and Python 3, we need to restrict the lines of code test to only run as Python 3.

python/ql/test/query-tests/Summary/LinesOfCode.expected

@@ -1 +1 @@
-| 38 |
+| 51 |