update php-fpm ssh2 ext version

php-fpm/Dockerfile

@@ -108,7 +108,7 @@ RUN if [ ${INSTALL_SSH2} = true ]; then \
     if [ $(php -r "echo PHP_MAJOR_VERSION;") = "5" ]; then \
         pecl install -a ssh2-0.13; \
     else \
-        pecl install -a ssh2-1.2; \
+        pecl install -a ssh2-1.3.1; \
     fi && \
     docker-php-ext-enable ssh2 \
 ;fi