eeschema - unfold from bus: double labels in popup menu

Using the "unfold from bus" right-clicking on a bus lists twice the bus member names.
Doing it with the shortcut "C" works correctly.

To reproduce the behaviour:
-Define a bus with bus->tools definitions and define
-Draw a bus on the schematic
-Put the name on the bus with "add a net label"
-right-click on the bus and choose "Unfold from bus"
--> probably now you will see "bus has no connections", but this is another bug: to workaround it, if the label is still black, drag the bus under the label, than it becomes blue and the bus name is set.

In the menu where to choose the net every bus member is reported twice

Also when the menu reports twice "bus has no connections" the second is selectable and unfolds a net with name "bus has no connections".

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Tested on commit d3dc7ade8ac8c59c14c457997893032bd15f3b9b

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Application: Eeschema
Version: (5.1.0-636-gd3dc7ade8), debug build
Libraries:
    wxWidgets 3.0.2
    libcurl/7.52.1 OpenSSL/1.0.2r zlib/1.2.8 libidn2/0.16 libpsl/0.17.0 (+libidn2/0.16) libssh2/1.7.0 nghttp2/1.18.1 librtmp/2.3
Platform: Linux 4.9.0-8-amd64 x86_64, 64 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.2 (wchar_t,wx containers,compatible with 2.8) GTK+ 2.24
    Boost: 1.69.0
    OpenCASCADE Community Edition: 6.8.0
    Curl: 7.52.1
    Compiler: GCC 6.3.0 with C++ ABI 1010

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON