Fix linter

.golangci.yml

@@ -9,6 +9,8 @@ linters-settings:
   cyclop:
     # the minimal code complexity to report
     max-complexity: 20
+  gocognit:
+    min-complexity: 45
 
 issues:
   exclude-use-default: false

crypto/message_getters.go

@@ -1,3 +1,4 @@
+//go:build !android
 // +build !android
 
 package crypto

helper/sign_detached.go

@@ -1,5 +1,5 @@
-// +build !ios
-// +build !android
+//go:build !ios && !android
+// +build !ios,!android
 
 package helper