[core] Add type annotations to component Python (#18697)

Co-authored-by: J. Nick Koston <nick@koston.org>

esphome/components/bme280_base/__init__.py

@@ -16,6 +16,8 @@ from esphome.const import (
     UNIT_HECTOPASCAL,
     UNIT_PERCENT,
 )
+from esphome.cpp_generator import MockObj
+from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core"]
 
@@ -84,7 +86,7 @@ CONFIG_SCHEMA_BASE = cv.Schema(
 ).extend(cv.polling_component_schema("60s"))
 
 
-async def to_code_base(config):
+async def to_code_base(config: ConfigType) -> MockObj:
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)