unfold from bus label rotate: screen is updated on next cursor movement.

Minor issue related to bugfix for #1852587:

When unfolding from bus and rotating the label using the shortcut "R", The screen is updated at the next mouse movement and not immediatly.

To replicate the behaviour:
-Unfold from bus ("C" shortcut)
-leave the mouse and Rotate label using the "R" shortcut: the label on screen (in the schematic) does not rotate until you move the cursor, while at the bottom of the screen the label "Orientation" property is updated correctly.
-move the cursor using the mouse or the cursor keys: now the label is redrawn on the schematic with the correct orientation.

Attached: a simple example-project.

Cheers,
Dino.

Master branch: affected
5.1 branch: not affected (does not have this function).

----------------------------------------------------
Application: Eeschema
Version: (5.99.0-424-gc186e7d39-dirty), release build
Libraries:
    wxWidgets 3.0.2
    libcurl/7.52.1 GnuTLS/3.5.8 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:
    Build date: Nov 26 2019 22:25:58
    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:
    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