feat(ssh_tunnel): Import/Export Databases with SSHTunnel credentials (#23099)

superset/databases/ssh_tunnel/models.py

@@ -68,6 +68,19 @@ class SSHTunnel(Model, AuditMixinNullable, ExtraJSONMixin, ImportExportMixin):
         EncryptedType(sa.String, app_config["SECRET_KEY"]), nullable=True
     )
 
+    export_fields = [
+        "server_address",
+        "server_port",
+        "username",
+        "password",
+        "private_key",
+        "private_key_password",
+    ]
+
+    extra_import_fields = [
+        "database_id",
+    ]
+
     @property
     def data(self) -> Dict[str, Any]:
         output = {