Add support for multiple MoveItConfigBuilder instaces (#1807) (#1808)

(cherry picked from commit 25d086c)

Co-authored-by: Marco Magri <94347649+MarcoMagriDev@users.noreply.github.com>

moveit_configs_utils/moveit_configs_utils/moveit_configs_builder.py

@@ -132,7 +132,7 @@ def to_dict(self):
 
 
 class MoveItConfigsBuilder(ParameterBuilder):
-    __moveit_configs = MoveItConfigs()
+    __moveit_configs: MoveItConfigs
     __robot_name: str
     __urdf_package: Path
     # Relative path of the URDF file w.r.t. __urdf_package
@@ -152,7 +152,7 @@ def __init__(
         package_name: Optional[str] = None,
     ):
         super().__init__(package_name or (robot_name + "_moveit_config"))
-        self.__moveit_configs.package_path = self._package_path
+        self.__moveit_configs = MoveItConfigs(package_path=self._package_path)
         self.__robot_name = robot_name
         setup_assistant_file = self._package_path / ".setup_assistant"