Fix Codespell complaints

Author: khoih-prog

README.md

@@ -478,7 +478,7 @@ Supposing the STM32 stm32 core version is 2.3.0. These files must be copied into
 - `~/.arduino15/packages/STM32/hardware/stm32/2.3.0/system/STM32F7xx/stm32f7xx_hal_conf_default.h` for Nucleo-144 STM32F7.
 
 Whenever a new version is installed, remember to copy this file into the new version directory. For example, new version is x.yy.zz,
-theses files must be copied into the corresponding directory:
+these files must be copied into the corresponding directory:
 
 - `~/.arduino15/packages/STM32/hardware/stm32/x.yy.zz/system/STM32F4xx/stm32f4xx_hal_conf_default.h`
 - `~/.arduino15/packages/STM32/hardware/stm32/x.yy.zz/system/STM32F7xx/stm32f7xx_hal_conf_default.h
@@ -494,7 +494,7 @@ Supposing the STM32 stm32 core version is 2.3.0. These files must be copied into
 - `~/.arduino15/packages/STM32/hardware/stm32/2.3.0/variants/STM32L0xx/L052R(6-8)T_L053R(6-8)T_L063R8T/NUCLEO_L053R8/variant.h` for Nucleo-64 NUCLEO_L053R8.
 
 Whenever a new version is installed, remember to copy this file into the new version directory. For example, new version is x.yy.zz,
-theses files must be copied into the corresponding directory:
+these files must be copied into the corresponding directory:
 
 - `~/.arduino15/packages/STM32/hardware/stm32/x.yy.zz/variants/STM32F7xx/F765Z(G-I)T_F767Z(G-I)T_F777ZIT/NUCLEO_F767ZI/variant.h`
 - `~/.arduino15/packages/STM32/hardware/stm32/x.yy.zz/variants/STM32L0xx/L052R(6-8)T_L053R(6-8)T_L063R8T/NUCLEO_L053R8/variant.h`
@@ -978,7 +978,7 @@ STM32_Pub
 Attempting MQTT connection to broker.emqx.io
 ...connected
 Published connection message successfully!
-Subcribed to: STM32_Sub
+Subscribed to: STM32_Sub
 MQTT Message Send : STM32_Pub => Hello from MQTT_ThingStream on ITSYBITSY_M4 with ESP8266-AT & ESP8266_AT_WebServer Library
 MQTT Message receive [STM32_Pub] Hello from MQTT_ThingStream on ITSYBITSY_M4 with ESP8266-AT & ESP8266_AT_WebServer Library
 MQTT Message Send : STM32_Pub => Hello from MQTT_ThingStream on ITSYBITSY_M4 with ESP8266-AT & ESP8266_AT_WebServer Library

platformio/platformio.ini

@@ -52,7 +52,7 @@ lib_deps =
 build_flags =
 ; set your debug output (default=Serial)
 ; -D DEBUG_ESP_PORT=Serial
-; comment the folowing line to enable WiFi debugging
+; comment the following line to enable WiFi debugging
 ; -D NDEBUG
 
 [env:ESP8266]