feat(comment): add comment on on interface method

spec/fixtures/comment/interface_many_method_input.go

@@ -0,0 +1,6 @@
+package main
+
+type Testinger interface {
+	Get(id string) int
+	Set(id string, val int)
+}

spec/fixtures/comment/interface_many_method_output.go

@@ -0,0 +1,7 @@
+package main
+
+type Testinger interface {
+	Get(id string) int
+	// Set 
+	Set(id string, val int)
+}

spec/fixtures/comment/interface_method_input.go

@@ -0,0 +1,5 @@
+package main
+
+type Testinger interface {
+	Method(input string) error
+}

spec/fixtures/comment/interface_method_output.go

@@ -0,0 +1,6 @@
+package main
+
+type Testinger interface {
+	// Method 
+	Method(input string) error
+}