Merge branch 'jjardon/doc_fix_deprecations' into 'master'

doc/bst2html.py: Fix deprecation warning

See merge request !727

doc/bst2html.py

@@ -29,7 +29,7 @@ import sys
 import re
 import shlex
 import subprocess
-from collections import Mapping
+from collections.abc import Mapping
 from contextlib import contextmanager
 from tempfile import TemporaryDirectory