Inference: handle Exact constraints with captured types properly

#KT-41818 Fixed

compiler/testData/codegen/box/fir/implicitNothingInDelegate.kt

@@ -0,0 +1,11 @@
+// TARGET_BACKEND: JVM_IR
+// WITH_RUNTIME
+
+// Note: this test passes in FIR but fails in FE 1.0 + IR
+fun box(): String {
+    val m1: Map<String, Any> = mapOf("foo" to "O")
+    val m2: Map<String, *> = mapOf("baz" to "K")
+    val foo: String by m1
+    val baz: String by m2
+    return foo + baz
+}