Cache downloaded PostgreSQL binaries during build

[qarmin]

Is your feature request related to a problem? Please describe.
We use this library in our project and we cache /target along with other folders to speed up compilation in CI.
Even with this setup, we’ve noticed that posgresql binaries are still being downloaded from GitHub (we use version =17.5.0), which sometimes causes random CI failures due github limits.

Describe the solution you'd like
Downloaded binaries should be saved to the filesystem, and on subsequent compilation runs, these files should be reused instead of downloading the same files repeatedly from GitHub.