fix(expressvpn): OpenVPN fragment option and add ciphers (#1047)

* Fragment was defined in `OpenVPNProviderSettings` but was not written to the OpenVPN configuration file.
* Added two additional ciphers to the configuration for ExpressVPN

Authored-by: barino86 <barino@mac.com>

internal/provider/utils/openvpn.go

@@ -136,6 +136,10 @@ func OpenVPNConfig(provider OpenVPNProviderSettings,
 		lines.add("mssfix", fmt.Sprint(mssFix))
 	}
 
+	if provider.Fragment > 0 {
+		lines.add("fragment", fmt.Sprint(provider.Fragment))
+	}
+
 	if provider.SndBuf > 0 {
 		lines.add("sndbuf", fmt.Sprint(provider.SndBuf))
 	}