Add exception log [FABJ-502] (#32)

Signed-off-by: lesleyannj <lesleyannj@hotmail.com>

Author: lesleyannjordan

src/main/java/org/hyperledger/fabric/sdk/Channel.java

@@ -5712,11 +5712,13 @@ public CompletableFuture<TransactionEvent> sendTransaction(Collection<? extends
 
                 CompletableFuture<TransactionEvent> ret = new CompletableFuture<>();
                 ret.completeExceptionally(lException != null ? new Exception(emsg, lException) : new Exception(emsg));
+                logger.error(emsg);
                 return ret;
             }
         } catch (Exception e) {
             CompletableFuture<TransactionEvent> future = new CompletableFuture<>();
             future.completeExceptionally(e);
+            logger.error(e);
             return future;
         }
     }