CI: Only creating packets on push to master

.github/workflows/build.yml

@@ -79,6 +79,7 @@ jobs:
     name: Create windows release
     runs-on: windows-latest
     needs: build
+    if: github.ref == 'refs/heads/master'
     steps:
       - uses: actions/checkout@v1
       - name: Download windows build
@@ -105,6 +106,7 @@ jobs:
     name: Create debian, rpm & arch releases
     runs-on: ubuntu-latest
     needs: build
+    if: github.ref == 'refs/heads/master'
     env:
       description: "A media browser"
       version: v0.0.1 #${{ github.ref }}

Kyoo.Core/Controllers/PluginManager.cs

@@ -21,7 +21,7 @@ namespace Kyoo.Core.Controllers
 		/// <summary>
 		/// The service provider. It allow plugin's activation.
 		/// </summary>
-		private IServiceProvider _provider;
+		private readonly IServiceProvider _provider;
 		/// <summary>
 		/// The configuration to get the plugin's directory.
 		/// </summary>