perf: cache PythonVersion objects

[melotic]

This adds caching to the PythonVersion class as profiling says this an incredibly expensive operation due to the amount of instances created and the expensive Regex. Testing with a small script on the data from our verification tests yields:

1317 of 1959 are duplicates
67.23% of the versions can be cached

Benchmarking on just the pip components from our verification tests with hyperfine shows notable performance gains:

Branch	Mean [s]	Min [s]	Max [s]	Relative
justinperez/pip-perf	5.106 ± 1.241	3.989	7.177	1.00
main	6.824 ± 1.101	4.267	8.765	1.34 ± 0.39

[github-actions]

👋 Hi! It looks like you modified some files in the Detectors folder.
You may need to bump the detector versions if any of the following scenarios apply:

• The detector detects more or fewer components than before
• The detector generates different parent/child graph relationships than before
• The detector generates different devDependencies values than before

If none of the above scenarios apply, feel free to ignore this comment 🙂