Consider Single Core Implementation

The current software implementation uses the Pico's second core (core1) to communicate with the BME688 device and the first core (core0) to communicate via Harp protocol. This is a somewhat power-intensive way of shipping this solution, and the second core may be responsible for adding a significant amount of heat.

The RP2040 at 125MHz consumes about ~30mA *per core* (datasheet pg 623), while the BMA688 consumes 12mA in its maximum power consumption state. Since we're using both cores, it's not unreasonable that the total power consumption of the RP2040 alone is upwards of 60mA.

Worth mentioning: the self-heating graphs in https://github.com/AllenNeuralDynamics/harp.device.environment-sensor/issues/2 were collected with a minimal implementation that only used 1 core. Since the updated PCBA shows only about 1C of self-heating, but later tests conducted elsewhere are measuring a ~5C increase, it is not unreasonable to assume that the second core is adding a significant amount of heat.

RP2040 [Datasheet](https://datasheets.raspberrypi.com/pico/pico-datasheet.pdf):


BME688 [Datasheet](https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bme688-ds000.pdf):