Make all MariaDB client plugins available in server plugin path

The MariaDB server has only one plugin directory (--plugin-dir). If the server is running as a replica, it will act as a client when connecting to the primary database instance. In those cases it may need to use the client plugins, but it is unable to load the client plugins in the same way as other client library using code would, and instead expects to find the plugins in the server plugin directory. Add the client plugins as symlinks there to prevent the server from failing to connect as client when using plugin dependant client features.

Changes in filelist

@@ -1061,6 +1061,9 @@
 drwxr-xr-x root/root ./usr/lib/mysql/plugin/auth_pam_tool_dir/  
 -rwxr-xr-x root/root ./usr/lib/mysql/plugin/auth_pam_tool_dir/auth_pam_tool  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/auth_pam_v1.so  
+lrwxrwxrwx root/root ./usr/lib/mysql/plugin/caching_sha2_password.so -> ../../x86_64-linux-gnu/libmariadb3/plugin/caching_sha2_password.so
+lrwxrwxrwx root/root ./usr/lib/mysql/plugin/client_ed25519.so -> ../../x86_64-linux-gnu/libmariadb3/plugin/client_ed25519.so
+lrwxrwxrwx root/root ./usr/lib/mysql/plugin/dialog.so -> ../../x86_64-linux-gnu/libmariadb3/plugin/dialog.so
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/disks.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/file_key_management.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/ha_archive.so  
@@ -1071,10 +1074,12 @@
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/handlersocket.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/locales.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/metadata_lock_info.so  
+lrwxrwxrwx root/root ./usr/lib/mysql/plugin/mysql_clear_password.so -> ../../x86_64-linux-gnu/libmariadb3/plugin/mysql_clear_password.so
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/password_reuse_check.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/query_cache_info.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/query_response_time.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/server_audit.so  
+lrwxrwxrwx root/root ./usr/lib/mysql/plugin/sha256_password.so -> ../../x86_64-linux-gnu/libmariadb3/plugin/sha256_password.so
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/simple_password_check.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/sql_errlog.so  
 -rw-r--r-- root/root ./usr/lib/mysql/plugin/type_mysql_json.so  
@@ -1533,8 +1538,6 @@