Merge pull request #425 from pmnxis/master

Update README.md typo issue on billmock (#424)

Author: therealprof

README.md

@@ -1306,7 +1306,7 @@ Work in progress crates. Help the authors make these crates awesome!
 - [Booster](https://github.com/quartiq/booster): Firmware for an RF power amplifier, including telemetry via MQTT and run-time configuration
 - [Thermostat EEM](https://github.com/quartiq/thermostat-eem): Firmware for a multi-channel temperature controller used in physics experiments
 - [Card/IO ECG](https://github.com/card-io-ecg/card-io-fw): Firmware for a business-card-sized ECG device with Wifi connectivity
-- [BillMcok](https://github.com/pmnxis/billmock-app-rs): Firmware for credit card terminal add-on hardware to install on Korean arcade machines
+- [BillMock](https://github.com/pmnxis/billmock-app-rs): Firmware for credit card terminal add-on hardware to install on Korean arcade machines
 - [LuLuu](https://github.com/fu5ha/luluu): Firmware for a custom RP2040-based display controller that streams animated images from a microSD card to a small LCD display. 
 
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