chore: remove unused platform app export

lib/crewai/src/crewai/agents/agent_builder/base_agent.py

@@ -9,7 +9,7 @@ import re
 from typing import TYPE_CHECKING, Annotated, Any, Final, Literal
 import uuid
 
-from crewai_core.platform_apps import PLATFORM_APPS, PlatformApp
+from crewai_core.platform_apps import PlatformApp
 from pydantic import (
     UUID4,
     BaseModel,
@@ -58,9 +58,6 @@ from crewai.utilities.rpm_controller import RPMController
 from crewai.utilities.string_utils import interpolate_only
 
 
-__all__ = ["PLATFORM_APPS"]
-
-
 if TYPE_CHECKING:
     from crewai.context import ExecutionContext
     from crewai.crew import Crew