[FIR Test] Migrate AbstractFirLoadCompiledKotlin to new test infrastructure

Also introduce two different modes for those tests:
- load metadata compiled with K1
- load metadata compiled with K2

compiler/testData/loadJava/compiledKotlinWithStdlib/mutability/LoadIterable.fir.txt

@@ -0,0 +1,10 @@
+public abstract interface LoadIterable<T> : R|kotlin/Any| {
+    public abstract fun getIterable(): R|kotlin/collections/MutableIterable<T>?|
+
+    public abstract fun getReadOnlyIterable(): R|kotlin/collections/Iterable<T>?|
+
+    public abstract fun setIterable(p0: R|kotlin/collections/MutableIterable<T>?|): R|kotlin/Unit|
+
+    public abstract fun setReadOnlyIterable(p0: R|kotlin/collections/Iterable<T>?|): R|kotlin/Unit|
+
+}

compiler/testData/loadJava/compiledKotlinWithStdlib/mutability/LoadIterableWithConflict.fir.txt

@@ -0,0 +1,6 @@
+public abstract interface LoadIterableWithConflict<T> : R|kotlin/Any| {
+    public abstract fun getIterable(): R|kotlin/collections/MutableIterable<T>?|
+
+    public abstract fun setIterable(p0: R|kotlin/collections/MutableIterable<T>?|): R|kotlin/Unit|
+
+}

compiler/testData/loadJava/compiledKotlinWithStdlib/mutability/LoadIterableWithNullability.fir.txt

@@ -0,0 +1,10 @@
+public abstract interface LoadIterableWithNullability<T> : R|kotlin/Any| {
+    public abstract fun getIterable(): R|kotlin/collections/MutableIterable<T>|
+
+    public abstract fun getReadOnlyIterable(): R|kotlin/collections/Iterable<T>|
+
+    public abstract fun setIterable(p0: R|kotlin/collections/MutableIterable<T>|): R|kotlin/Unit|
+
+    public abstract fun setReadOnlyIterable(p0: R|kotlin/collections/Iterable<T>|): R|kotlin/Unit|
+
+}

compiler/testData/loadJava/compiledKotlinWithStdlib/mutability/LoadIterableWithPropagation.fir.txt

@@ -0,0 +1,26 @@
+public abstract interface LoadIterableWithPropagation : R|kotlin/Any| {
+    public abstract interface LoadIterable<T> : R|kotlin/Any| {
+        public abstract fun getIterable(): R|kotlin/collections/MutableIterable<T>?|
+
+        public abstract fun getReadOnlyIterable(): R|kotlin/collections/Iterable<T>?|
+
+        public abstract fun setIterable(p0: R|kotlin/collections/MutableIterable<T>?|): R|kotlin/Unit|
+
+        public abstract fun setReadOnlyIterable(p0: R|kotlin/collections/Iterable<T>?|): R|kotlin/Unit|
+
+    }
+
+    public open class LoadIterableImpl<T> : R|test/LoadIterableWithPropagation.LoadIterable<T>| {
+        public open fun getIterable(): R|kotlin/collections/MutableIterable<T>?|
+
+        public open fun getReadOnlyIterable(): R|kotlin/collections/Iterable<T>?|
+
+        public open fun setIterable(p0: R|kotlin/collections/MutableIterable<T>?|): R|kotlin/Unit|
+
+        public open fun setReadOnlyIterable(p0: R|kotlin/collections/Iterable<T>?|): R|kotlin/Unit|
+
+        public constructor<T>(): R|test/LoadIterableWithPropagation.LoadIterableImpl<T>|
+
+    }
+
+}