Release v1.8 (#685)

chore: release v1.8.0

chore: update changelog

Merge pull request #658 from graph-gophers/update-federation-example

update federation example

Allow deprecated directive on arguments (#541)

Refactor trace package (#513)

Remove dependency for graphql-go on OpenTracing and OpenTelemetry except
 where those tracers are explicitly configured for use.

validation: fix bug in maxDepth fragment spread logic (#492)

Accepting value Json in parameter of request's body in custom Scalar (#…

…467)

Accept JSON value in resolver args

Merge pull request #456 from savaki/master

errors.Errorf preserves original error similar to fmt.Error