Provisioning DefaultDocuments in folders in DocumentSets causes duplicated content

Description

When using the PnP Provisioning engine to provision Document Sets with DefaultDocuments (aka Default Content) in subfolders, each default document living in a subfolder will be duplicated. Subsequent runs of the provisioning template will add 2 instances of each file every run. Note that I have reproduced this using PnP.PowerShell, but it is a pnpframework issue.

Steps to reproduce

The simplest way to reproduce this issue is to test through PnP.PowerShell with a SiteTemplate. I've created a minimal testcase which you find attached here: TestCase-DocumentSet.zip

1. Download and uncompress the testcase to a folder on your machine
2. Pick an existing site, or create a new site. Can be a group or communication site, does not matter
3. Run the provisioning engine with the template.xml as input, if you are testing this using PnP.PowerShell you can run the following

Connect-PnPOnline -Url <url to test site> -Interactive
Set-PnPSite -NoScriptSite $false    # required in order to provision DefaultDocuments
Invoke-PnPSiteTemplate -Path ./template.xml
Set-PnPSite -NoScriptSite $true

Expected result

Under default content in the content type, I expect to find two (2) files,
Folder 1/doc1.docx
Folder 2/doc2.docx

Actual results

Each file is uploaded twice

Observations

The test for duplicate defaultdocuments checks the file by name. The condition d.Name != doc.Name will always return true if the Default Document in the template is defined like so

<pnp:DefaultDocument Name="Folder 1/doc1.docx" ContentTypeID="0x0101" FileSourcePath="./doc1.docx" />

Since the documentSetTemplate (i.e. CSOM/pnpframework object) will always have the Name be the filename without the path.

Start in src/lib/PnP.Framework/Provisioning/ObjectHandlers/ObjectContentType.cs around the duplicate default document check at line 387. Reproduce the issue with the attached TestCase-DocumentSet.zip and template.xml, focusing on DefaultDocument entries whose Name includes a subfolder path. Done means repeated provisioning no longer duplicates Folder 1/doc1.docx or Folder 2/doc2.docx.