Add support for nested classes to UI #649

[volivan239]

Description

Changed the behavior of plugin on classes with nested classes. Now, when launching UTBot for a class, its nested classes will be shown in dialog (in addition to its methods). This behavior holds both when launching from editor and from 'Project' tool window.

Fixes #649

Type of Change

• Minor bug fix (non-breaking small changes)

How Has This Been Tested?

Manual Scenario

Launch UTBot from different scopes of the class below (both from editor and from 'Project' tool window) -- should work as expected.

public class SomeClass {
    public class InnerClass {
        private int y;
        InnerClass(int y) {
            this.y = y;
        }
        public class DeepInner {
            public int f() {
                if (y == 1) return 1;
                return 2;
            }
        }
        public int g() {
            return 2;
        }
    }
    public int h() {
        return 3;
    }
}

Checklist (remove irrelevant options):

This is the author self-check list

• The change followed the style guidelines of the UTBot project
• Self-review of the code is passed
• The change contains enough commentaries, particularly in hard-to-understand areas
• New documentation is provided or existed one is altered
• No new warnings
• New tests have been added
• All tests pass locally with my changes