Duplicated output when running Scancode in verbose mode

### Description

When running Scancode in verbose mode (`-v` flag), the files listed in output are duplicated and it looks they are scanned two times.
According to @pombredanne, this is a bug and needs to be reported.

### How To Reproduce

I experienced this bug when scanning https://github.com/Azure/azure-sdk-for-net.git with the command:
`scancode --copyright --license --info --strip-root --timeout 300 --max-in-memory 5000 --processes 3 . --json-pp /tmp/result.json -v`

The output looks like this:
```
[...]
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/README.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/README.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/CONTRIBUTING.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/CONTRIBUTING.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/SECURITY.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/SECURITY.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/NOTICE.txt
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/NOTICE.txt
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/.config/dotnet-tools.json
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/.config/dotnet-tools.json
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/swagger_to_sdk_config.json
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/swagger_to_sdk_config.json
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/SUPPORT.md
Scanned: /home/nino/IdeaProjects/Tests/azure-sdk-for-net/SUPPORT.md
[...]
```

### System configuration

> For bug reports, it really helps us to know:

* What OS are you running on? Debian Bullseye
* What version of scancode-toolkit was used to generate the scan file? 31.1.0
* What installation method was used to install/run scancode? pip