functional-tests: remove outdated tests that do not use internal fields

The test case called 'internalFieldOfStructCanBeAccessed' initially
used internal fields, but the usage was removed when it stopped to
compile.

The fields 'someInteger' and 'someLong' are public in public type:
```
struct SomeStructWithInternalMembers {
    someInteger: Int
    someLong: Long
```

Signed-off-by: Patryk Wrobel <183546751+pwrobeldev@users.noreply.github.com>

Author: pwrobeldev

functional-tests/functional/android/src/test/java/com/here/android/test/VisibilityAttributeTest.java

@@ -40,16 +40,11 @@ public void internalConstructorOfClassCanBeCalled() {
     SomeClassWithInternalMembers someObject = new SomeClassWithInternalMembers();
   }
 
-  @Test
-  public void internalFieldOfStructCanBeAccessed() {
-    SomeStructWithInternalMembers someObject = new SomeStructWithInternalMembers(21);
-    assertEquals(21, someObject.someInteger);
-    assertEquals(444, someObject.someLong);
-  }
-
   @Test
   public void internalFreeArgsCtorCanBeCalled() {
     SomeStructWithInternalFreeArgsCtor someObject = new SomeStructWithInternalFreeArgsCtor(33);
+
+    // Note: 'someObject.someString' is a public field of public structure.
     assertEquals("Special string", someObject.someString);
   }
 
@@ -61,6 +56,8 @@ public void internalAllArgsCtorCanBeCalled() {
   @Test
   public void internalFieldCtorCanBeCalled() {
     SomeStructWithInternalFieldConstructor someObject = new SomeStructWithInternalFieldConstructor(77);
+
+    // Note: 'someObject.someString' is a public field of public structure.
     assertEquals("QAZWSX", someObject.someString);
   }
 
@@ -70,11 +67,6 @@ public void valueOfInternalEnumCanBeAccessed() {
     assertEquals(SomeInternalEnum.TWO, someObject);
   }
 
-  @Test
-  public void internaInterfaceFromJavaCanBeUsed() {
-    SomeStructWithInternalMembers someObject = new SomeStructWithInternalMembers(21);
-  }
-
   @Test
   public void internalExceptionCanBeThrown() {
     SomethingBadHappenedException exception = assertThrows(SomethingBadHappenedException.class, () -> {