Document the importance of Win drivers installation

[noopkat]

Note: This issue is ideal for folks wishing to make their first code contribution/pull request to AVRGirl Arduino, or it might even be their first open source pull request ever! Please do not open a PR for this if you're an existing code/docs contributor to AVRGirl Arduino. Thanks ❤️

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The Issue:

Plugging in an Arduino isn't an out-of-the-box-working experience for Windows users. Installing the Arduino IDE and the included drivers is an important first step before being able to use AVRGirl Arduino.

In the installation instructions, I'd love to see a small section in this project's README.md file added for Windows, with extra details documented on how to get the above 2 steps up and running.

There is already some great docs on how users can do this on this Arduino website page. It would be sufficient enough to share this link in the AVRGirl Arduino README, with some friendly language advising following only steps 1-4 is necessary. Keeping to the current writing personality/style of the README is encouraged.

Please follow the code contribution guidelines as set out in this repo's contributing guide.

Thank you @byronhulcher for reporting this via Test Pilot! ✨