Remove constraints containing stub types after completion of the common system of a builder inference call

^KT-49285 Fixed

compiler/testData/codegen/box/inference/builderInference/kt49285.kt

@@ -0,0 +1,25 @@
+// DONT_TARGET_EXACT_BACKEND: WASM
+// IGNORE_BACKEND_FIR: JVM_IR
+// WITH_RUNTIME
+
+import kotlin.experimental.ExperimentalTypeInference
+
+class Foo<T> {
+    fun add(x: T) {}
+}
+
+@OptIn(ExperimentalTypeInference::class)
+fun <K1> myBuilder1(@BuilderInference builder: Foo<K1>.() -> Foo<K1>): Foo<K1> = Foo<K1>().apply { builder() }
+
+@OptIn(ExperimentalTypeInference::class)
+fun <K2> myBuilder2(@BuilderInference builder: Foo<K2>.() -> Unit): Foo<K2> = Foo<K2>().apply(builder)
+
+fun box(): String {
+    val result1 = myBuilder1 {
+        add(null)
+        myBuilder2 {
+            add("")
+        }
+    }
+    return "OK"
+}