Do not render declarations from other modules in diagnostic tests

Because PackageViewDescriptor may consist of several package fragments from
different modules (see LazyPackageViewDescriptorImpl#fragments), we now filter
out fragments from irrelevant modules before rendering them into the .txt

compiler/testData/diagnostics/tests/callableReference/classVsPackage.txt

@@ -42,20 +42,10 @@ package
 
 package a {
 
-    public final class b {
-        // -- Module: <m1> --
-    }
-
     package a.b {
-
-        public final class c {
-            // -- Module: <m2> --
-        }
     }
 }
 
 package test {
     public fun test(): kotlin.reflect.KFunction1<a.b.c, kotlin.Unit>
 }
-
-