Problems under concurrency

[chrisgraham]

Version: 3.4.2

Bug Description

When running PHPStan with parallelism on a large project, it is possible for the cache to corrupt due to very frequent reads and writes.

Steps To Reproduce

Not really possible.

Expected Behavior

PHPStan should run normally.

Possible Solution

Making a PR request that introduces new configuration options to mitigate the problem when running on dev environments under stress.