feat: make SubmitAsync<T> method public

[tsanton]

Is your feature request related to a problem? Please describe.
There are some queries that must be run highly optimised, or that is hard to write/not yet supported by the provider, and it would be great to be able to submit those from raw gremlin.

Describe the solution you'd like
A public method, maybe under the .AsAdmin()-api, allowing you to SubmitAsync<T>(maybe QueryAsync (with return) and ExecuteAsync(no return). It would be nice if it accepted serialization settings, but all in all it will be fine to just communicate the need for where T: Vertex and an expected return format for serialization (maybe .project('id','label','properties').by(id).by(label).by(map(properties().group().by(key()).by(value()))))?

Describe alternatives you've considered
Continue using the Gremlin.Net.Driver, but it's cumbersome to maintain multiple clients and package versions (as well as conflicts with CosmosDB with the 3.7.* dependency of Gremlin.Net.Driver).

Consider sponsoring me
We'd be happy to purchase some hours of your time to have this available in the near future!

[danielcweber]

@tsanton Please have a look at https://docs.gremlinq.net/extensions/, specifically the section about the Gremlinq.Extensions.GroovyScripts package.