FIR DFA: add more called-in-place tests

compiler/fir/analysis-tests/testData/resolve/cfg/flowFromInplaceLambda3.kt

@@ -13,7 +13,7 @@ fun atLeastOnce(x: () -> Unit) {
 }
 
 fun exactlyOnce(x: () -> Unit) {
-    contract { callsInPlace(x, InvocationKind.AT_LEAST_ONCE) }
+    contract { callsInPlace(x, InvocationKind.EXACTLY_ONCE) }
     x()
 }
 
@@ -30,6 +30,14 @@ fun test1() {
     x.<!UNRESOLVED_REFERENCE!>inc<!>()
 }
 
+fun test1m() {
+    var x: Any?
+    x = ""
+    x.length
+    unknown { x = "" }
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+}
+
 fun test2() {
     var x: Any?
     x = ""