Update repositories.txt (#6707)

https://github.com/adafruit/Adafruit_MLX90632

Author: ladyada

repositories.txt

@@ -707,6 +707,7 @@ https://github.com/adafruit/Adafruit_Microbit
 https://github.com/adafruit/Adafruit_MiniMLX90614
 https://github.com/adafruit/Adafruit_MLX90393_Library
 https://github.com/adafruit/Adafruit_MLX90395
+https://github.com/adafruit/Adafruit_MLX90632
 https://github.com/adafruit/Adafruit_MLX90640
 https://github.com/adafruit/Adafruit_MMA8451_Library
 https://github.com/adafruit/Adafruit_MMC56x3