[Analysis API] add diagnostic test for FP expose diagnostic from library

^KT-64468
^KT-62891

analysis/analysis-api/testData/components/diagnosticsProvider/diagnostics/overrideProtectedClassReturnFromLibrary.kt

@@ -0,0 +1,16 @@
+// IGNORE_FE10
+// KT-64503
+
+// MODULE: lib
+// MODULE_KIND: LibraryBinary
+// FILE: TestExposeTypeLib.kt
+abstract class TestExposeTypeLib {
+    protected abstract fun returnProtectedClass(): ProtectedClass?
+    protected class ProtectedClass
+}
+
+// MODULE: main(lib)
+// FILE: usage.kt
+class Usage : TestExposeTypeLib() {
+    override fun returnProtectedClass(): ProtectedClass? = null
+}

analysis/analysis-api/testData/components/diagnosticsProvider/diagnostics/overrideProtectedClassReturnFromLibrary.standalone.fir.txt

@@ -0,0 +1 @@
+Diagnostics from elements:

analysis/analysis-api/testData/components/diagnosticsProvider/diagnostics/overrideProtectedClassReturnFromLibrary.txt

@@ -0,0 +1,4 @@
+Diagnostics from elements:
+  for PSI element of type KtNamedFunction at (15,5-64)
+    EXPOSED_FUNCTION_RETURN_TYPE      text ranges: [(103,123)]
+      PSI: KtNamedFunction at (15,5-64)