Can't extract netfxsdk.msi

**Describe the bug**
A clear and concise description of what the bug is.

Extracting the MSI from .NET FX SDK 1.1 gets the following error:

```
---------------------------
MSI Error!
---------------------------
Please report this error at https://github.com/activescott/lessmsi/issues . Include the exact error message and how to get a copy of the msi you're working with.

The following error occured extracting the MSI: System.Exception: Error copying file 'C:\Users\Adam\Desktop\netfxsd1.cab' to 'C:\Users\Adam\Desktop\netfxsd1.cab'. System error information:'The operation completed successfully.

'

at LessIO.Strategies.Win32.Win32FileSystemStrategy.Copy(Path source, Path dest)

at LessMsi.Msi.Wixtracts.CabsFromMsiToDisk(Path msi, Database msidb, String outputDir)

at LessMsi.Msi.Wixtracts.ExtractFiles(Path msi, String outputDir, MsiFile[] filesToExtract, AsyncCallback progressCallback)

at LessMsi.Gui.MainForm.btnExtract_Click(Object sender, EventArgs e)
---------------------------
OK
---------------------------

```

**To Reproduce**
Steps to reproduce the behavior:
1. Download https://download.microsoft.com/download/5/2/0/5202f918-306e-426d-9637-d7ee26fbe507/setup.exe (https://www.microsoft.com/en-us/download/confirmation.aspx?id=16217)
2. Extract the msi and CAB from setup.exe using 7zip
3. Extract with lessmsi-gui
4. See error

**Expected behavior**
A clear and concise description of what you expected to happen.

**Screenshots**
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**Desktop (please complete the following information):**
Windows 10 1809, lessmsi 1.6.1.0

**Additional context**
Add any other context about the problem here.

Start from the reported call stack: LessMsi.Gui.MainForm.btnExtract_Click -> LessMsi.Msi.Wixtracts.ExtractFiles -> LessMsi.Msi.Wixtracts.CabsFromMsiToDisk -> LessIO.Strategies.Win32.Win32FileSystemStrategy.Copy. Reproduce with the linked Microsoft setup.exe, extract the MSI/CAB with 7zip, then run lessmsi-gui extract again to confirm the same path-copy exception. Inspect the Win32 file strategy path handling for source/destination resolution. Done when extraction of that netfxsdk.msi/cab completes successfully without the reported System.Exception popup.

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