Update go.mod version to 1.19

Relates to pion/webrtc#2292

Author: edaniels

go.mod

@@ -8,4 +8,10 @@ require (
 	golang.org/x/net v0.22.0
 )
 
-go 1.13
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
+
+go 1.19