Fix DebugServices.UnitTests VersionData failures

Fix the underlying problem where the binary can not be reliably downloaded in order to map into the address space to find the special version string on Linux or the PE version resource on Windows.

```
xunit.console Warning: 0 : DownLoadPE: module /home/mikem/diagnostics/.dotnet-test/shared/Microsoft.NETCore.App/6.0.0-rc.2.21464.21/libhostpolicy.so has no index timestamp/filesize
xunit.console Error: 0 : HttpSymbolStore: An error occurred while sending the request. libhostpolicy.so - 'https://msdl.microsoft.com/download/symbols/libhostpolicy.so/elf-buildid-c35b973c1876c3af7895b034ad4f36b73230b52a/libhostpolicy.so'
xunit.console Warning: 0 : DownLoadPE: module /home/mikem/diagnostics/.dotnet-test/shared/Microsoft.NETCore.App/6.0.0-rc.2.21464.21/libhostpolicy.so has no index timestamp/filesize
xunit.console Information: 0 : GetVersionString: not found in ELF file 00007FD49ADA9000
xunit.console Information: 0 : Module.GetVersion no version string
xunit.console Information: 0 : CompareMembers VersionData: expected '6.0.21.46421' == actual ''
```

Remove the code used by the DebugServices.UnitTests in TestDataReader.cs around line 310 that makes these failures a warning instead of an error.