[Native][tests] Read stdout/stderr of test process in separate threads

Sometimes, the launched test process can't finish on Windows if stdout and stderr threads are not read completely. The proper approach here would be to spawn two threads for constantly reading stdout & stderr while the process in being executed.

native/native.tests/testData/samples/standalone_notr_long_running.kt

@@ -0,0 +1,31 @@
+// KIND: STANDALONE_NO_TR
+
+import kotlin.math.E
+import kotlin.math.sqrt
+import kotlin.system.getTimeMillis
+import kotlin.test.assertTrue
+
+// Runs for ~60 seconds. Prints a short message to stdout every second.
+fun main() {
+    for (i in 0..60) {
+        println("Iteration $i")
+        sleep(1000)
+    }
+    println("Done.")
+}
+
+private fun sleep(millis: Int) {
+    assertTrue(millis > 0)
+
+    val endTimeMillis = getTimeMillis() + millis
+    do {
+        // Emulate intensive computations to spend CPU time.
+        for (i in 1..100) {
+            for (j in 1..100) {
+                storage = if (storage.toLong() % 2 == 0L) sqrt(i.toDouble() * j.toDouble()) else E * i / j
+            }
+        }
+    } while (getTimeMillis() < endTimeMillis)
+}
+
+private var storage: Double = 0.0