Added Relate and Graph Semantics tests

[Du-z]

Added a test for creating Relations and the querying them via Graph Semantics.

The RPC queries are failing while the REST ones pass.

The failing query RELATE $thing1->hasOtherThing->$thing2; produces the following JSON:

{
  "id": "qrBo3bkT",
  "method": "query",
  "params": [
    "RELATE $thing1->hasOtherThing->$thing2;",
    {
      "thing1": "object1:VbNy93UFUX",
      "thing2": "object2:VbNy93UFUX"
    }
  ]
}

Tweaking the query slightly to look like RELATE $thing1 -> hasOtherThing -> $thing2; or RELATE ($thing1)->hasOtherThing->($thing2) passes.

{
  "id": "n3pJe7ja",
  "method": "query",
  "params": [
    "RELATE $thing1 -> hasOtherThing -> $thing2;",
    {
      "thing1": "object1:7VWcpn9fO1",
      "thing2": "object2:7VWcpn9fO1"
    }
  ]
}

The two RPC documents looks functionally the same

[Du-z]

Looks like it is a bug, I have worked around it in this test

surrealdb/surrealdb#1313

[ProphetLamb]

Looking good! Thanks for the PR