Delete deprecated test files that only tested exir.capture behavior

[JacobSzwejbka]

Summary:
Remove test_capture.py (tested exir.capture directly), test_tracer.py
(tested CaptureConfig flags like _unlift and enable_dynamic_shape),
test_backends.py (covered by test_backends_lifted.py), and
Remove corresponding build targets from TARGETS/BUCK files.

Differential Revision: D95605525

[pytorch-bot]

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❌ 1 New Failure, 2 Cancelled Jobs, 1 Unrelated Failure

As of commit fcd30c9 with merge base baa9888 ():

NEW FAILURE - The following job has failed:

• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t c5777856137c4b8d040209b7b71926c69cff85610c6c94637d1a283a793c414a /exec failed with exit code 92

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• periodic (gh)
• pull / unittest / windows / windows-job (gh)

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / unittest-editable / windows / windows-job (gh) (matched win rule in flaky-rules.json)
  ##[error]The operation was canceled.

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[meta-codesync]

@JacobSzwejbka has exported this pull request. If you are a Meta employee, you can view the originating Diff in D95605525.

[github-actions]

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[lucylq]

Thanks!