Add wildcard support to AddLegacySource

[pakrym]

Azure SDKs produce activities that have tags and links set and don't need extra enrichment.

For client level spans we use the client and method name as activity name (i.e. BlobClient.Download) so it's impractical to use the existing AddLegacySource(string name) to collect them as customers would need to add every individual method they use.

Feature request:

Add wildcard support to AddLegacySource the same way it exists in AddSource so customers can write

.AddLegacySource("Azure.*");

[pakrym]

cc @cijothomas

[lmolkova]

I tried to list all possible legacy activity names.

For EventHub it's bearable:

  .AddLegacySource("EventHubs.Message")
  .AddLegacySource("EventHubProducerClient.Send")
  .AddLegacySource("EventProcessor.Process")
  .AddLegacySource("EventProcessor.Checkpoint")

But Storage does this: $"{nameof(BlobBaseClient)}.{nameof(Download)}" and it's a huge list to make. So I believe there is no workaround here.