Use global imports for ESPHome (#24158)

* Use global import for ESPHome

* Add aioesphomeapi to test requirements

aioesphomeapi is also shipped as a pure-python wheel, so this should not impact test install time

homeassistant/components/esphome/switch.py

@@ -1,16 +1,14 @@
 """Support for ESPHome switches."""
 import logging
-from typing import TYPE_CHECKING, Optional
+from typing import Optional
+
+from aioesphomeapi import SwitchInfo, SwitchState
 
 from homeassistant.components.switch import SwitchDevice
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.helpers.typing import HomeAssistantType
 
-from . import EsphomeEntity, platform_async_setup_entry, esphome_state_property
-
-if TYPE_CHECKING:
-    # pylint: disable=unused-import
-    from aioesphomeapi import SwitchInfo, SwitchState  # noqa
+from . import EsphomeEntity, esphome_state_property, platform_async_setup_entry
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -18,9 +16,6 @@ _LOGGER = logging.getLogger(__name__)
 async def async_setup_entry(hass: HomeAssistantType,
                             entry: ConfigEntry, async_add_entities) -> None:
     """Set up ESPHome switches based on a config entry."""
-    # pylint: disable=redefined-outer-name
-    from aioesphomeapi import SwitchInfo, SwitchState  # noqa
-
     await platform_async_setup_entry(
         hass, entry, async_add_entities,
         component_key='switch',
@@ -33,11 +28,11 @@ class EsphomeSwitch(EsphomeEntity, SwitchDevice):
     """A switch implementation for ESPHome."""
 
     @property
-    def _static_info(self) -> 'SwitchInfo':
+    def _static_info(self) -> SwitchInfo:
         return super()._static_info
 
     @property
-    def _state(self) -> Optional['SwitchState']:
+    def _state(self) -> Optional[SwitchState]:
         return super()._state
 
     @property