Remove tests for avconv animation writers.

anntzer · anntzer · commit 5217ca21f600 · 2021-12-15T00:45:05.000+01:00
The writer classes themselves have already been removed in Py3.5, but
the tests were kept.
diff --git a/lib/matplotlib/tests/test_animation.py b/lib/matplotlib/tests/test_animation.py
@@ -138,8 +138,6 @@ def isAvailable(cls):
 WRITER_OUTPUT = [
     ('ffmpeg', 'movie.mp4'),
     ('ffmpeg_file', 'movie.mp4'),
-    ('avconv', 'movie.mp4'),
-    ('avconv_file', 'movie.mp4'),
     ('imagemagick', 'movie.gif'),
     ('imagemagick_file', 'movie.gif'),
     ('pillow', 'movie.gif'),
