Fix SDLPrinter to include operation type for queries with variables

Author: Shane32

src/GraphQLParser.Tests/Visitors/SDLPrinterFromParsedTextTests.cs

@@ -1066,6 +1066,7 @@ public void UTF8_MemoryStream_Runs_Synchronously()
     [Theory]
     [InlineData("{ field1 }", "{\n  field1\n}\n")]
     [InlineData("query { field1 }", "{\n  field1\n}\n")]
+    [InlineData("query ($arg: String) { field1 }", "query ($arg: String){\n  field1\n}\n")]
     [InlineData("query q1 { field1 }", "query q1 {\n  field1\n}\n")]
     [InlineData("mutation { field1 }", "mutation {\n  field1\n}\n")]
     [InlineData("mutation m1 { field1 }", "mutation m1 {\n  field1\n}\n")]

src/GraphQLParser/Visitors/SDLPrinter.cs

@@ -262,7 +262,7 @@ protected override async ValueTask VisitFieldAsync(GraphQLField field, TContext
     protected override async ValueTask VisitOperationDefinitionAsync(GraphQLOperationDefinition operationDefinition, TContext context)
     {
         await VisitAsync(operationDefinition.Comments, context).ConfigureAwait(false);
-        if (operationDefinition.Name is not null || operationDefinition.Operation != OperationType.Query)
+        if (operationDefinition.Name is not null || operationDefinition.Operation != OperationType.Query || operationDefinition.Variables is not null)
         {
             await VisitAsync(LiteralNode.Wrap(GetOperationType(operationDefinition.Operation)), context).ConfigureAwait(false);
             await context.WriteAsync(" ").ConfigureAwait(false);