uwp: sign appx package

.github/workflows/uwp.yml

@@ -44,6 +44,7 @@ jobs:
           makeappx.exe unpack /p .\flycast_1.0.0.0_x64.msix /d tmp
           copy ..\..\..\Release\*.dll tmp
           makeappx pack /d tmp /p ..\..\..\artifact\flycast.appx
+          signtool sign /f ..\..\..\..\shell\uwp\sign_cert.pfx /p ' ${{ secrets.SIGN_CERT_PWD }}' /v /fd SHA256 ..\..\..\artifact\flycast.appx
 
       - uses: actions/upload-artifact@v2
         with:

shell/uwp/package.appxManifest

@@ -4,7 +4,7 @@
 	xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10"
 	IgnorableNamespaces="uap mp">
 
-	<Identity Name="AF75D068-D5AC-3D3C-B52A-2791C2F3491A" Publisher="CN=Flyinghead, O=Flycast, C=US" Version="1.0.0.0" />
+	<Identity Name="AF75D068-D5AC-3D3C-B52A-2791C2F3491A" Publisher="CN=Flyinghead" Version="1.0.0.0" />
 	<mp:PhoneIdentity PhoneProductId="AF75D068-D5AC-3D3C-B52A-2791C2F3491A" PhonePublisherId="00000000-0000-0000-0000-000000000000"/>
 	<Properties>
 		<DisplayName>Flycast</DisplayName>