Fix small mistake in the Readme of kotlinx-coroutines-test (#1865)
Fix small mistake in the Readme of kotlinx-coroutines-test (#1865)

There was a small mistake in the Readme of kotlinx-coroutines-test. A lateinit variable evaluated to null at the beginning.
Kotlin/kotlinx.coroutines,Kotlin/kotlinx.coroutines,Kotlin/kotlinx.coroutines,Kotlin/kotlinx.coroutines,Kotlin/kotlinx.coroutines