[esp32] Accept unquoted minimum_chip_revision values (#15785)

esphome/components/esp32/__init__.py

@@ -1222,7 +1222,7 @@ FRAMEWORK_SCHEMA = cv.Schema(
                 cv.Optional(CONF_IGNORE_EFUSE_CUSTOM_MAC, default=False): cv.boolean,
                 cv.Optional(CONF_IGNORE_EFUSE_MAC_CRC, default=False): cv.boolean,
                 cv.Optional(CONF_MINIMUM_CHIP_REVISION): cv.one_of(
-                    *ESP32_CHIP_REVISIONS
+                    *ESP32_CHIP_REVISIONS, string=True
                 ),
                 cv.Optional(CONF_SRAM1_AS_IRAM, default=False): cv.boolean,
                 # DHCP server is needed for WiFi AP mode. When WiFi component is used,