fix(pypi): allow pip_compile to work with read-only sources #2712
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The validating
py_testgenerated bycompile_pip_requirementschokes when the sourcerequirements.txtis stored read-only, such as when managed by the Perforce Helix Core SCM. Thoughdependency_resolvermakes a temporary copy of this file, it does so w/shutil.copywhich preserves the original read-only file mode. To address this, this commit replacesshutil.copywith ashutil.copyfileobjsuch that the temporary file is created w/ permissions according to the user's umask.Resolves (#2608).