chore: add support for UUID in CloudClientExecutor

Author: gagangupt16

google-cloud-spanner-executor/src/main/java/com/google/cloud/executor/spanner/CloudClientExecutor.java

@@ -2897,6 +2897,9 @@ private com.google.spanner.executor.v1.ValueList buildStruct(StructReader struct
           case DATE:
             value.setDateDaysValue(daysFromDate(struct.getDate(i)));
             break;
+          case UUID:
+            value.setStringValue(struct.getUuid(i).toString());
+            break;
           case NUMERIC:
             String ascii = struct.getBigDecimal(i).toPlainString();
             value.setStringValue(ascii);