Fix SDLPrinter to include operation type for queries with variables

[Shane32]

Description

Fixes an issue in SDLPrinter where anonymous query operations with variables were not printing the query keyword.

According to the GraphQL specification, when an operation includes variable definitions, the operation type must be explicitly declared even for query operations without a name.

Changes

• Modified VisitOperationDefinitionAsync to check if Variables is present in addition to checking for operation name or non-query operation type
• Added test case in SDLPrinterFromParsedTextTests to verify the fix handles anonymous queries with variables correctly

Example

Before:

($arg: String){
  field1
}

After:

query ($arg: String){
  field1
}

[gao-artur]

I think you added it to a wrong milestone

[gao-artur]

I think you added it to a wrong milestone

Oh, it's a parser repo. Nevermind.