Added extra public field in clue object

[andreamah]

Description:

When testing this test: https://github.com/adafruit/Adafruit_CircuitPython_CLUE/blob/master/examples/clue_slideshow.py, I found that there should be a public field in CLUE for the display. I made the small change.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

Testing:

https://github.com/adafruit/Adafruit_CircuitPython_CLUE/blob/master/examples/clue_slideshow.py

Checklist:

• My code follows the style guidelines of this project
• My code has been formatted with npm run format and passes the checks in npm run check
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[vandyliu]

It took a while but it was worth the read. I learned a lot. Great change!