Actually apply the pre-commit fixers to the codebase.

This can be redone manually with
`pre-commit run --all`

While the pre-commit hook could be merged to run locally,
it is much cleaner to align all the files to best-practice
syntax in a single commit. It is also required for server-side
validation.

client/config_test.go

@@ -1,11 +1,12 @@
 package client_test
 
 import (
-	"github.com/stretchr/testify/require"
-	"heckel.io/ntfy/client"
 	"os"
 	"path/filepath"
 	"testing"
+
+	"github.com/stretchr/testify/require"
+	"heckel.io/ntfy/client"
 )
 
 func TestConfig_Load(t *testing.T) {