Include Arduino.h to fix compiler warnings

[LuAPi]

Related issue # and issue behavior

Compiler generates warnings

.arduino15/packages/arduino/tools/CMSIS-Atmel/1.2.0/CMSIS/Device/ATMEL/samd21/include/samd21g18a.h:226:0: warning: "LITTLE_ENDIAN" redefined
 #define LITTLE_ENDIAN          1

.arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/arm-none-eabi/include/machine/endian.h:17:0: note: this is the location of the previous definition
 #define LITTLE_ENDIAN _LITTLE_ENDIAN

from files

BME280/src/BME280.cpp:31
BME280/src/BME280I2C.cpp:31

When building for Arduino Nano 33 IoT

Description of changes/fixes

Including Arduino.h stops these warnings being generated.

@mention a person to review

Steps to test

Build with and without these changes in an environment that doesn't supress warnings.

Any outstanding TODOs or known issues