docs: remove broken logo link from GSoC 2017 page

The RawGit CDN service (cdn.rawgit.com) has been permanently shut down,
causing the AboutCode logo image to return a 404 error. This commit
removes the broken image reference from the archived GSoC 2017
documentation page.

Fixes #231

Signed-off-by: Gyan Ranjan Panda <gyanranjanpanda@gmail.com>

Author: Gyan Ranjan Panda

docs/source/archive/gsoc/org_pages/gsoc_2017.rst

@@ -1,12 +1,6 @@
 Google Summer of Code 2017
 ==========================
 
-
-.. image:: https://cdn.rawgit.com/wiki/nexB/aboutcode/aboutcode_logo.svg
-   :target: http://www.aboutcode.org/
-   :alt: AboutCode Logo
-
-
 Welcome to AboutCode! This year AboutCode is a mentoring Organization for
 the Google Summer of Code 2017 edition.