fix: resolve UnboundLocalError in apm prune crashing all prune operations

[Copilot]

apm prune failed unconditionally with cannot access local variable 'get_lockfile_path' where it is not associated with a value, breaking all prune-related integration tests.

Description

A duplicate from ..deps.lockfile import get_lockfile_path inside the prune() function body shadowed the module-level import. Python treats any name assigned (including via import) within a function as local throughout the entire function scope — causing an UnboundLocalError when the name was referenced earlier in the same function, before the inner import statement was reached.

# Before — duplicate inner import made `get_lockfile_path` an unbound local
from ..deps.lockfile import LockFile, get_lockfile_path  # module-level

def prune(...):
    lockfile = LockFile.read(get_lockfile_path(...))  # UnboundLocalError here ↑
    ...
    if pruned_keys:
        from ..deps.lockfile import get_lockfile_path   # ← this shadowed the module import
        lockfile_path = get_lockfile_path(...)

Fix: remove the redundant inner import; the module-level import is sufficient.

Type of change

• Bug fix
• New feature
• Documentation
• Maintenance / refactor

Testing

• Tested locally
• All existing tests pass
• Added tests for new functionality (if applicable)

Original prompt

Fix the failing GitHub Actions workflow Integration Tests (Linux)
Analyze the workflow logs, identify the root cause of the failure, and implement a fix.
Job ID: 66955159225
Job URL: https://github.com/microsoft/apm/actions/runs/23051934848/job/66955159225

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[Copilot]

Pull request overview

This PR removes a redundant local import in the apm prune command, relying on the existing module-level import for get_lockfile_path.

Changes:

• Remove the nested from ..deps.lockfile import get_lockfile_path import inside the if pruned_keys: block.