[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/enum/enumWithInnerClasses.fir.txt

@@ -0,0 +1,33 @@
+public final enum class Enum : R|kotlin/Enum<test/Enum>| {
+    public final fun f(): R|kotlin/Int|
+
+    public final val c: R|kotlin/Int|
+        public get(): R|kotlin/Int|
+
+    private constructor(): R|test/Enum|
+
+    public final inner class Inner : R|kotlin/Any| {
+        public test/Enum.constructor(): R|test/Enum.Inner|
+
+    }
+
+    public final class Nested : R|kotlin/Any| {
+        public constructor(): R|test/Enum.Nested|
+
+    }
+
+    public abstract interface Trait : R|kotlin/Any| {
+    }
+
+    public final static enum entry ENTRY1: R|test/Enum|
+    public final static enum entry ENTRY2: R|test/Enum|
+    public final static fun values(): R|kotlin/Array<test/Enum>| {
+    }
+
+    public final static fun valueOf(value: R|kotlin/String|): R|test/Enum| {
+    }
+
+    public final static val entries: R|kotlin/enums/EnumEntries<test/Enum>|
+        public get(): R|kotlin/enums/EnumEntries<test/Enum>|
+
+}