treewide: Fix mysql alias deprecation breakage

62733b37b4 broke evaluation in all
places `pkgs.mysql` was used. Fix this by changing all occurrences to
`pkgs.mariadb`.

(cherry picked from commit 59e0120aa5c1241d48048afa615e25c65d7e366d)

nixos/modules/services/backup/mysql-backup.nix

@@ -4,7 +4,7 @@ with lib;
 
 let
 
-  inherit (pkgs) mysql gzip;
+  inherit (pkgs) mariadb gzip;
 
   cfg = config.services.mysqlBackup;
   defaultUser = "mysqlbackup";
@@ -20,7 +20,7 @@ let
   '';
   backupDatabaseScript = db: ''
     dest="${cfg.location}/${db}.gz"
-    if ${mysql}/bin/mysqldump ${if cfg.singleTransaction then "--single-transaction" else ""} ${db} | ${gzip}/bin/gzip -c > $dest.tmp; then
+    if ${mariadb}/bin/mysqldump ${if cfg.singleTransaction then "--single-transaction" else ""} ${db} | ${gzip}/bin/gzip -c > $dest.tmp; then
       mv $dest.tmp $dest
       echo "Backed up to $dest"
     else

nixos/modules/services/databases/mysql.nix

@@ -34,7 +34,7 @@ in
 
       package = mkOption {
         type = types.package;
-        example = literalExample "pkgs.mysql";
+        example = literalExample "pkgs.mariadb";
         description = "
           Which MySQL derivation to use. MariaDB packages are supported too.
         ";

nixos/modules/services/video/epgstation/default.nix

@@ -27,7 +27,7 @@ let
 
     # NOTE: Use password authentication, since mysqljs does not yet support auth_socket
     if [ ! -e /var/lib/epgstation/db-created ]; then
-      ${pkgs.mysql}/bin/mysql -e \
+      ${pkgs.mariadb}/bin/mysql -e \
         "GRANT ALL ON \`${cfg.database.name}\`.* TO '${username}'@'localhost' IDENTIFIED by '$DB_PASSWORD';"
       touch /var/lib/epgstation/db-created
     fi
@@ -224,7 +224,7 @@ in
 
     services.mysql = {
       enable = mkDefault true;
-      package = mkDefault pkgs.mysql;
+      package = mkDefault pkgs.mariadb;
       ensureDatabases = [ cfg.database.name ];
       # FIXME: enable once mysqljs supports auth_socket
       # ensureUsers = [ {

nixos/modules/services/web-apps/keycloak.nix

@@ -728,7 +728,7 @@ in
 
         services.postgresql.enable = lib.mkDefault createLocalPostgreSQL;
         services.mysql.enable = lib.mkDefault createLocalMySQL;
-        services.mysql.package = lib.mkIf createLocalMySQL pkgs.mysql;
+        services.mysql.package = lib.mkIf createLocalMySQL pkgs.mariadb;
       };
 
   meta.doc = ./keycloak.xml;

nixos/modules/services/web-apps/tt-rss.nix

@@ -644,7 +644,7 @@ let
 
     services.mysql = mkIf mysqlLocal {
       enable = true;
-      package = mkDefault pkgs.mysql;
+      package = mkDefault pkgs.mariadb;
       ensureDatabases = [ cfg.database.name ];
       ensureUsers = [
         {