[FIR-TEST] Move analysis tests to separate module

compiler/fir/analysis-tests/testData/resolve/cfg/when.kt

@@ -0,0 +1,18 @@
+// !DUMP_CFG
+fun test_1(x: Int) {
+    val y = when {
+        x == 1 -> 10
+        x % 2 == 0 -> 20
+        1 - 1 == 0 -> return
+        else -> 5
+    }
+}
+
+interface A
+interface B
+
+fun test_2(x: Any?) {
+    if (x is A && x is B) {
+        x is A
+    }
+}