Upgrade certbot (1.7.0 -> 1.9.0)

roles/matrix-nginx-proxy/defaults/main.yml

@@ -227,7 +227,7 @@ matrix_ssl_domains_to_obtain_certificates_for: []
 
 # Controls whether to obtain production or staging certificates from Let's Encrypt.
 matrix_ssl_lets_encrypt_staging: false
-matrix_ssl_lets_encrypt_certbot_docker_image: "certbot/certbot:{{ matrix_ssl_architecture }}-v1.7.0"
+matrix_ssl_lets_encrypt_certbot_docker_image: "certbot/certbot:{{ matrix_ssl_architecture }}-v1.9.0"
 matrix_ssl_lets_encrypt_certbot_docker_image_force_pull: "{{ matrix_ssl_lets_encrypt_certbot_docker_image.endswith(':latest') }}"
 matrix_ssl_lets_encrypt_certbot_standalone_http_port: 2402
 matrix_ssl_lets_encrypt_support_email: ~