Reorganize diagnostics tests with stdlib and reflect

DiagnosticsTestWithStdLib now require stdlib only.
Move test data accordingly.
The only test that required kotlin-reflect is transformed into
codegen box test.

compiler/testData/codegen/box/regressions/kt9345.kt

@@ -0,0 +1,15 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+// WITH_REFLECT
+
+// KT-9345 Type inference failure
+fun Class<*>.foo(): Any? = kotlin.objectInstance
+
+
+object OK {
+    override fun toString(): String = "OK"
+}
+
+fun box(): String {
+    return OK::class.java.foo().toString()
+}