[mono] MarshalingPInvokeScanner tolerates DLLs without metadata (#89430)

* Acquire MetadataReader under try. * Logging failed metadata access. * Update src/tasks/MonoTargetsTasks/MarshalingPInvokeScanner/MarshalingPInvokeScanner.cs Co-authored-by: Theodore Tsirpanis <teo@tsirpanis.gr> --------- Co-authored-by: Theodore Tsirpanis <teo@tsirpanis.gr>

Author: jandupej

src/tasks/MonoTargetsTasks/MarshalingPInvokeScanner/MarshalingPInvokeScanner.cs

@@ -106,6 +106,10 @@ private bool IsAssemblyIncompatible(string assyPath, MinimalMarshalingTypeCompat
  {
  using FileStream file = new FileStream(assyPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
  using PEReader peReader = new PEReader(file);
+ if (!peReader.HasMetadata)
+ {
+ return false;
+ }
  MetadataReader mdtReader = peReader.GetMetadataReader();
 
  foreach(CustomAttributeHandle attrHandle in mdtReader.CustomAttributes)