Resolve DeprecationWarning by pkg_resources by switching to importlib…

…_metadata

"Creating a LegacyVersion has been deprecated and will be removed in the next major release"

setup.py

@@ -56,7 +56,8 @@ def read(fname):
             'pytest-flask',
             'pytest-flake8',
             'bumpversion',
-            'autopep8'
+            'autopep8',
+            'importlib_metadata'
         ]
     },
     entry_points={

tests/test_cli.py

@@ -4,7 +4,7 @@
 import random
 import re
 import os.path
-import pkg_resources
+import importlib_metadata
 import json
 from click.testing import CliRunner
 import annif.cli
@@ -806,5 +806,5 @@ def test_version_option():
         annif.cli.cli, ['--version'])
     assert not result.exception
     assert result.exit_code == 0
-    version = pkg_resources.require('annif')[0].version
+    version = importlib_metadata.version('annif')
     assert result.output.strip() == version.strip()