[BUG] Multiple recorded test classes within same test assembly causes CI failures

[scbedd]

Describe the bug

As is happening in #1384

We fixed the issue with test assemblies crashing during the downloading of the proxy (refined in #1313), but we need to do the same for the restore action that happens at the beginning of every testcase.

This will likely be using the common file locking, and explicitly adding a restore to the proxy startup code.

Expected behavior

No failures to checkout due to simultaneous file access.

Actual behavior

No random crashes in CI if multiple recorded test classes in same test assembly.

Reproduction Steps

See description.

Environment

No response