Fix #2673: JSON file encoding in absubmit

First, it's best to open the file as binary so the JSON module itself
can figure out how to decode it (it will just use UTF-8). Then, we can
use `load` instead of `loads` to avoid needing to read the file
explicitly ourselves.

beetsplug/absubmit.py

@@ -133,8 +133,8 @@ def _get_analysis(self, item):
                     item=item, error=e
                 )
                 return None
-            with open(filename) as tmp_file:
-                analysis = json.loads(tmp_file.read())
+            with open(filename, 'rb') as tmp_file:
+                analysis = json.load(tmp_file)
             # Add the hash to the output.
             analysis['metadata']['version']['essentia_build_sha'] = \
                 self.extractor_sha

docs/changelog.rst

@@ -35,6 +35,8 @@ Fixes:
   music. :bug:`2667`
 * :doc:`/plugins/chroma`: Fix a crash when running the ``submit`` command on
   Python 3 on Windows with non-ASCII filenames. :bug:`2671`
+* :doc:`/plugins/absubmit`: Fix an occasional crash on Python 3 when the AB
+  analysis tool produced non-ASCII metadata. :bug:`2673`
 
 For developers: