Fix time format RFC3339 in version arduino#283

Author: u5surf

Diff for: cli/version/version.go

@@ -19,6 +19,7 @@ package version
 
 import (
 	"fmt"
+	"time"
 
 	"github.com/arduino/arduino-cli/cli"
 	"github.com/spf13/cobra"
@@ -49,7 +50,7 @@ func run(cmd *cobra.Command, args []string) {
 		Command:   cmd.Parent().Name(),
 		Version:   cli.VersionInfo.VersionString,
 		Commit:    cli.VersionInfo.Commit,
-		BuildDate: cli.VersionInfo.BuildDate.String(),
+		BuildDate: cli.VersionInfo.BuildDate.Format(time.RFC3339),
 	}
 	if cli.OutputJSONOrElse(res) {
 		fmt.Printf("%s\n", cli.VersionInfo)