Change path to install nginx configuration

Directories such as /etc/nginx/sites-{enabled, available and similar}
are not available for nginx package comes from official nginx repository.

Ubuntu source may create this directory
refer1 : ubuntu distributes nginx with a file "nginx-common.dirs"
which lists these directories
https://git.launchpad.net/ubuntu/+source/nginx/tree/debian/nginx-common.dirs?h=ubuntu/jammy-updates

By default, nginx recognizes configuration files in /etc/nginx/conf.d/
Just change the destination path to install nginx configuration files

Author: kkimurak

assets/runtime/functions

@@ -23,10 +23,10 @@ GITLAB_ACTIONCABLE_CONFIG="${GITLAB_INSTALL_DIR}/config/cable.yml"
 GITLAB_SECRETS_CONFIG="${GITLAB_INSTALL_DIR}/config/secrets.yml"
 GITLAB_ROBOTS_CONFIG="${GITLAB_INSTALL_DIR}/public/robots.txt"
 GITLAB_SHELL_CONFIG="${GITLAB_SHELL_INSTALL_DIR}/config.yml"
-GITLAB_NGINX_CONFIG="/etc/nginx/sites-enabled/gitlab"
-GITLAB_CI_NGINX_CONFIG="/etc/nginx/sites-enabled/gitlab_ci"
-GITLAB_REGISTRY_NGINX_CONFIG="/etc/nginx/sites-enabled/gitlab-registry"
-GITLAB_PAGES_NGINX_CONFIG="/etc/nginx/sites-enabled/gitlab-pages"
+GITLAB_NGINX_CONFIG="/etc/nginx/conf.d/gitlab.conf"
+GITLAB_CI_NGINX_CONFIG="/etc/nginx/conf.d/gitlab_ci.conf"
+GITLAB_REGISTRY_NGINX_CONFIG="/etc/nginx/conf.d/gitlab-registry.conf"
+GITLAB_PAGES_NGINX_CONFIG="/etc/nginx/conf.d/gitlab-pages.conf"
 GITLAB_PAGES_CONFIG="${GITLAB_INSTALL_DIR}/gitlab-pages-config"
 GITLAB_GITALY_CONFIG="${GITLAB_GITALY_INSTALL_DIR}/config.toml"