Do not show console on Windows

* Update wkhtmltopdf.go

Get rid of console window appearing on Windows

* hide cmd console on windows

* hide cmd console on windows

cmdcfg.go

@@ -0,0 +1,8 @@
+//go:build !windows
+// +build !windows
+
+package wkhtmltopdf
+
+import "os/exec"
+
+func cmdConfig(cmd *exec.Cmd) {}

cmdcfg_windows.go

@@ -0,0 +1,13 @@
+//go:build windows
+// +build windows
+
+package wkhtmltopdf
+
+import (
+	"os/exec"
+	"syscall"
+)
+
+func cmdConfig(cmd *exec.Cmd) {
+	cmd.SysProcAttr = &syscall.SysProcAttr{CreationFlags: 0x08000000, HideWindow: true}
+}

wkhtmltopdf.go

@@ -331,6 +331,9 @@ func (pdfg *PDFGenerator) run(ctx context.Context) error {
 	// create command
 	cmd := exec.CommandContext(ctx, pdfg.binPath, pdfg.Args()...)
 
+	// configure the commande (different for each OS, windows only for now (hides the cmd console))
+	cmdConfig(cmd)
+
 	// set stderr to the provided writer, or create a new buffer
 	var errBuf *bytes.Buffer
 	cmd.Stderr = pdfg.stdErr