Increase the poll rate for BDX diagnostic log downloads. (#33741)

The default rate used by bdx::Responder is once every 500ms, which means you
maybe manage to get 1kB/s of log through the network.

We should allow this process to go faster.  Switch to once every 50ms, to match
all the other BDX transfers we have around that poll like this.

src/protocols/bdx/BdxTransferDiagnosticLog.cpp

@@ -25,6 +25,12 @@ namespace {
 // Max block size for the BDX transfer.
 constexpr uint32_t kMaxBdxBlockSize = 1024;
 
+// How often we poll our transfer session.  Sadly, we get allocated on
+// unsolicited message, which makes it hard for our clients to configure this.
+// But the default poll interval is 500ms, which makes log downloads extremely
+// slow.
+constexpr System::Clock::Timeout kBdxPollInterval = System::Clock::Milliseconds32(50);
+
 // Timeout for the BDX transfer session..
 constexpr System::Clock::Timeout kBdxTimeout = System::Clock::Seconds16(5 * 60);
 constexpr TransferRole kBdxRole              = TransferRole::kReceiver;
@@ -95,7 +101,8 @@ CHIP_ERROR BdxTransferDiagnosticLog::OnMessageReceived(Messaging::ExchangeContex
         mTransferProxy.SetFabricIndex(fabricIndex);
         mTransferProxy.SetPeerNodeId(peerNodeId);
         auto flags(TransferControlFlags::kSenderDrive);
-        ReturnLogErrorOnFailure(Responder::PrepareForTransfer(mSystemLayer, kBdxRole, flags, kMaxBdxBlockSize, kBdxTimeout));
+        ReturnLogErrorOnFailure(
+            Responder::PrepareForTransfer(mSystemLayer, kBdxRole, flags, kMaxBdxBlockSize, kBdxTimeout, kBdxPollInterval));
     }
 
     return TransferFacilitator::OnMessageReceived(ec, payloadHeader, std::move(payload));