Missing signature for darwin-arm64 pet binary

The pet binary for darwin-arm64 is not signed which makes it hard to allowlist with tools like [Santa](https://northpole.dev/).

```bash
$ codesign -dv ~/.vscode/extensions/ms-python.vscode-python-envs-1.36.0-darwin-arm64/python-env-tools/bin/pet
Executable=/Users/[username]/.vscode/extensions/ms-python.vscode-python-envs-1.36.0-darwin-arm64/python-env-tools/bin/pet
Identifier=pet-2bba45dba123fe6f
Format=Mach-O thin (arm64)
CodeDirectory v=20400 size=43949 flags=0x20002(adhoc,linker-signed) hashes=1370+0 location=embedded
Signature=adhoc
Info.plist=not bound
TeamIdentifier=not set
Sealed Resources=none
Internal requirements=none
```

Related Issues / PRs:
* https://github.com/microsoft/vscode-python/pull/23931
* https://github.com/microsoft/python-environment-tools/issues/139