Restore IsWindows variable assignment (#6722) (#6790)

Signed-off-by: Nicola Scattaglia <scattaglia.nicola.work@gmail.com>

modules/setting/setting.go

@@ -16,6 +16,7 @@ import (
 	"os/exec"
 	"path"
 	"path/filepath"
+	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -407,6 +408,7 @@ func getWorkPath(appPath string) string {
 }
 
 func init() {
+	IsWindows = runtime.GOOS == "windows"
 	// We can rely on log.CanColorStdout being set properly because modules/log/console_windows.go comes before modules/setting/setting.go lexicographically
 	log.NewLogger(0, "console", "console", fmt.Sprintf(`{"level": "trace", "colorize": %t, "stacktraceLevel": "none"}`, log.CanColorStdout))