Add GraphQL detection (#980)

* Add GraphQL detection

* Change the abbreviation to `GQL`

* Fix the `TestMacros` test case

* Try to fix the security issues reported by Snyk

* Run `go mod tidy` in `agent` directory

* Upgrade `golang.org/x/crypto`

* Downgrade `golang.org/x/crypto`

* Downgrade `golang.org/x/crypto`

* Downgrade `golang.org/x/crypto`

* Upgrade to `github.com/vektah/gqlparser/v2 v2.4.2`

* Run `go mod tidy`

* Replace `github.com/vektah/gqlparser/v2` with its fork `github.com/mertyildiran/gqlparser/v2` to fix the vulns

* Upgrade the `github.com/mertyildiran/gqlparser/v2 v2.4.6`

* Don't upgrade `golang.org/x/net`

tap/extensions/http/graphql.go

@@ -0,0 +1,31 @@
+package http
+
+import (
+	"encoding/json"
+
+	"github.com/mertyildiran/gqlparser/v2/ast"
+	"github.com/mertyildiran/gqlparser/v2/parser"
+)
+
+func isGraphQL(request map[string]interface{}) bool {
+	if postData, ok := request["postData"].(map[string]interface{}); ok {
+		if postData["mimeType"] == "application/json" {
+			if text, ok := postData["text"].(string); ok {
+				var data map[string]interface{}
+				if err := json.Unmarshal([]byte(text), &data); err != nil {
+					return false
+				}
+
+				if query, ok := data["query"].(string); ok {
+
+					_, err := parser.ParseQuery(&ast.Source{Name: "ff", Input: query})
+					if err == nil {
+						return true
+					}
+				}
+			}
+		}
+	}
+
+	return false
+}