Fixing GrpcWorkerChannel concurrency bug (#10999)

Author: surgupta-msft

release_notes.md

@@ -5,3 +5,4 @@
 -->
 
 - Added the option to exclude test data from the `/functions` endpoint API response (#10943)
+- Fixing GrpcWorkerChannel concurrency bug

src/WebJobs.Script.Grpc/Channel/GrpcWorkerChannel.cs

@@ -65,8 +65,8 @@ internal partial class GrpcWorkerChannel : IRpcWorkerChannel, IDisposable
         private bool _disposing;
         private WorkerInitResponse _initMessage;
         private RpcWorkerChannelState _state;
-        private IDictionary<string, Exception> _functionLoadErrors = new Dictionary<string, Exception>();
-        private IDictionary<string, Exception> _metadataRequestErrors = new Dictionary<string, Exception>();
+        private IDictionary<string, Exception> _functionLoadErrors = new ConcurrentDictionary<string, Exception>();
+        private IDictionary<string, Exception> _metadataRequestErrors = new ConcurrentDictionary<string, Exception>();
         private ConcurrentDictionary<string, ExecutingInvocation> _executingInvocations = new();
         private IDictionary<string, BufferBlock<ScriptInvocationContext>> _functionInputBuffers = new ConcurrentDictionary<string, BufferBlock<ScriptInvocationContext>>();
         private ConcurrentDictionary<string, TaskCompletionSource<bool>> _workerStatusRequests = new ConcurrentDictionary<string, TaskCompletionSource<bool>>();