Don't quote field names in object value strings

[edsrzf]

Doing this caused problems when introspecting default values in gqlgen.

For example, say you had this schema:

type Query {
  field(arg: Arg! = {argField: 1}): Int
}

input Arg {
  argField: Int
}

When introspecting, you'd get back results that looked like this:

{
   ...
   "args": [
     {
        name: "arg",
        defaultValue: "{\"argField\": 1}"
        ...
     }
   ]
   ...

The quotes around argField cause problems because they create invalid GraphQL input literal syntax.

[vektah]

Nice find. Have you tested this in graphql playground to make sure it's can display with this format?

[coveralls]

Coverage remained the same at 90.834% when pulling ad58dda on edsrzf:fix-object-value-string into f119686 on vektah:master.

[edsrzf]

Yes, it works. The playground was what led to me discovering the problem in the first place, since the playground was complaining about invalid syntax in the default value.