Strip out certain files from ddtrace

[tianchu]

What does this PR do?

Remove the following files from ddtrace, because they contain code like os.execl, which cause security scans to fail for certain customers. These files are not directly used by the Forwarder.

Motivation

Let security scans to pass for affected customers.

Testing Guidelines

Additional Notes

Types of changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• This PR impacts documentation, and it has been updated (or a ticket has been logged)
• This PR's changes are covered by the automated tests
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[hghotra]

LGTM 👍