validator: fix total test number statistic

[QuerthDP]

When running Validator with subset of tests, the total number of tests in statistics was incorrect.
It represented all tests in a test file, not only those selected.

This fix changes the total number of tests to only the tests being run. The pass results should show total = launched = ok.

Fixes: VECTOR-392

[QuerthDP]

Cargo Deny failed although I'm not sure what would be the fix for it. Seems like it fails on master as well.
@ewienik could you look at that?

[ewienik]

Cargo Deny failed although I'm not sure what would be the fix for it. Seems like it fails on master as well. @ewienik could you look at that?

It seems that rustls-pemfile is unmaintained now. We need to switch to rustls-pki-types

error[unmaintained]: rustls-pemfile is unmaintained
    ┌─ /home/runner/work/vector-store/vector-store/Cargo.lock:255:1
    │
255 │ rustls-pemfile 2.2.0 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unmaintained advisory detected
    │
    ├ ID: RUSTSEC-2025-0134
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2025-0134
    ├ The rustls-pemfile crate is no longer maintained. The repository has been archived since August
      2025, and users are encouraged to depend directly on the underlying PEM parsing code included
      in rustls-pki-types since 1.9.0. The latest version of rustls-pemfile is in fact a thin wrapper
      around the same code used in rustls-pki-types, so migrating should be straightforward.
      
      The new API is represented by the [`PemObject`][PemObject] trait, which provides methods for
      reading a single or multiple PEM objects from a file or byte slice.

[ewienik]

It seems that rustls-pemfile is unmaintained now. We need to switch to rustls-pki-types

I've just created VECTOR-396

[QuerthDP]

Changelog:

• rebased on master