[FIR-TEST] Move analysis tests to separate module

compiler/fir/analysis-tests/testData/resolveWithStdlib/inference/complexConstraintSystem.kt

@@ -0,0 +1,5 @@
+class Inv<X>(val x: X)
+
+fun test_0(list: List<Int>, b: Boolean) {
+    val x = list.mapNotNull { if (b) Inv(it) else null }.first().x
+}