Remove language_version for black

Let's see if getting the default helps.

'linting' on Linux is failing with:

    RuntimeError: failed to find interpreter for Builtin discover of python_spec='python3.8'

Author: nicoddemus

.github/workflows/main.yml

@@ -31,7 +31,7 @@ jobs:
     - name: Install tox
       run: |
         python -m pip install --upgrade pip
-        pip install tox
+        pip install --upgrade virtualenv tox
     - name: Test
       run: |
         tox -e ${{ matrix.tox_env }}

.pre-commit-config.yaml

@@ -5,7 +5,6 @@ repos:
     hooks:
       - id: black
         args: [--safe, --quiet]
-        language_version: python3.8
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v2.2.3
     hooks: