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.

cmd/app_test.go

@@ -3,11 +3,12 @@ package cmd
 import (
 	"bytes"
 	"encoding/json"
-	"github.com/urfave/cli/v2"
-	"heckel.io/ntfy/client"
 	"os"
 	"strings"
 	"testing"
+
+	"github.com/urfave/cli/v2"
+	"heckel.io/ntfy/client"
 )
 
 // This only contains helpers so far