[python] Do not fetch tokens for regression tests (during pytest)

[dimakuv]

Description of the changes

This was a leftover after #1093

How to test this PR?

CI.

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This change is 

[woju]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion, not enough approvals from maintainers (2 more required), not enough approvals from different teams (1 more required, approved so far: Intel) (waiting on @dimakuv)

a discussion (no related file):
How those files are cleaned? Because when you start the app, they're created anyway.

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[dimakuv]

Reviewable status: 1 of 2 files reviewed, 2 unresolved discussions, not enough approvals from maintainers (2 more required), not enough approvals from different teams (1 more required, approved so far: Intel), "fixup! " found in commit messages' one-liners (waiting on @woju)

a discussion (no related file):

Previously, woju (Wojtek Porczyk) wrote…

How those files are cleaned? Because when you start the app, they're created anyway.

Done. There is a problem that Ninja build system doesn't know about these .token files since they are generated by Gramine itself. So had to add an explicit removal, not sure it's a "clean" approach.

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a discussion (no related file):
It turns out that our regression-test Python scripts do not use the gramine-sgx wrapper (that generates token if needed), but instead use loader binary directly. So the token files are not generated in that case.

See:

• gramine/python/graminelibos/regression.py

  Line 186 in 32504a9

  return self.pal_path / 'loader'

• gramine/python/graminelibos/regression.py

  Line 222 in 32504a9

  cmd = [*prefix, fspath(self.loader_path), fspath(self.libpal_path), 'init', *args]

I thought this PR would be simple, but it turns out too complicated. I don't want to spend time on this non-problem anymore. If noone minds, I'll just close it (after some timeout).

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[dimakuv]

Closing, see my other comment. Too complicated.