feat: using preview.kurtosis.com (#2337)

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enclave-manager/server/server.go

@@ -98,8 +98,7 @@ func (c *WebServer) CreateRepositoryWebhook(ctx context.Context, req *connect.Re
  owner := packageIdSplit[len(packageIdSplit)-2]
  repo := packageIdSplit[len(packageIdSplit)-1]
  client := github.NewClient(nil).WithAuthToken(c.githubAccessToken)
- // TODO change this to Kurtosis when required
- webhookUrl := "https://preview.imagenix.org/webhook"
+ webhookUrl := "https://preview.kurtosis.com/webhook"
  contentTypeJson := "json"
  hook := &github.Hook{
  Name: github.String("web"),