Add playground file for StateFlow lecture

Author: LukasLechnerDev

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/flow/stateflow/1-stateflow.kt

@@ -0,0 +1,25 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.flow.stateflow
+
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+suspend fun main() {
+
+    val counter = MutableStateFlow(0)
+
+    println(counter.value)
+
+    coroutineScope {
+        repeat(10_000) {
+            launch {
+                counter.update { currentValue ->
+                    currentValue + 1
+                }
+            }
+        }
+    }
+
+    println(counter.value)
+}