Do not output empty non-root packages in tests with txt

Mostly to avoid listing every internal package in
kotlin-stdlib/kotlin-reflect, as in
https://github.com/JetBrains/kotlin/blob/acd5b62148d797ffd24c4811d1d663f0c1ae7885/compiler/testData/diagnostics/testsWithUnsignedTypes/conversions/conversionOfSignedToUnsigned.txt#L144

compiler/testData/diagnostics/tests/qualifiedExpression/GenericClassVsPackage.txt

@@ -44,12 +44,6 @@ package
 public fun test(/*0*/ ab_c: a.b.c): kotlin.Unit
 public fun test2(/*0*/ ab_c: a.b.c): kotlin.Unit
 
-package a {
-
-    package a.b {
-    }
-}
-
 
 // -- Module: <top_m1> --
 package
@@ -91,6 +85,3 @@ package
 
 public fun test(/*0*/ a_b: a.b): kotlin.Unit
 public fun test2(/*0*/ _ab: a.b): kotlin.Unit
-
-package a {
-}

compiler/testData/diagnostics/tests/qualifiedExpression/PackageVsClass.txt

@@ -55,12 +55,6 @@ package
 public fun test(/*0*/ a_b: a.b): kotlin.Unit
 public fun test2(/*0*/ ab_c: a.b.c): kotlin.Unit
 
-package a {
-
-    package a.b {
-    }
-}
-
 
 // -- Module: <m1> --
 package
@@ -109,9 +103,3 @@ package
 
 public fun test(/*0*/ a_b: a.b): kotlin.Unit
 public fun test2(/*0*/ ab_c: a.b.c): kotlin.Unit
-
-package a {
-
-    package a.b {
-    }
-}

compiler/testData/diagnostics/tests/qualifiedExpression/PackageVsClass2.txt

@@ -30,9 +30,6 @@ package a {
 // -- Module: <m2> --
 package
 
-package a {
-}
-
 package test {
     public val x: [ERROR : Type for a.b()]
 
@@ -48,9 +45,6 @@ package test {
 // -- Module: <m3> --
 package
 
-package a {
-}
-
 package test {
     public fun foo(/*0*/ i: a.a): kotlin.Unit
 }

compiler/testData/diagnostics/tests/qualifiedExpression/visibleClassVsQualifiedClass.txt

@@ -38,9 +38,6 @@ package some {
 // -- Module: <m3> --
 package
 
-package a {
-}
-
 package other {
     public fun test(/*0*/ a_: [ERROR : a.b]): kotlin.Unit