Update k6 GitHub repo URL

Author: Ivan Mirić

README.md

@@ -1,5 +1,5 @@
 # xk6-output-kafka
-Is extracted the original [kafka output](https://k6.io/docs/results-visualization/apache-kafka) from [k6](https://github.com/loadimpact/k6) so it can be used with [xk6](https://github.com/k6io/xk6).
+Is extracted the original [kafka output](https://k6.io/docs/results-visualization/apache-kafka) from [k6](https://github.com/k6io/k6) so it can be used with [xk6](https://github.com/k6io/xk6).
 
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