Bump pyupgrade from 2.20.0 to 2.21.0 (#64)

* Bump pyupgrade from 2.20.0 to 2.21.0

Bumps [pyupgrade](https://github.com/asottile/pyupgrade) from 2.20.0 to 2.21.0.
- [Release notes](https://github.com/asottile/pyupgrade/releases)
- [Commits](asottile/pyupgrade@v2.20.0...v2.21.0)

---
updated-dependencies:
- dependency-name: pyupgrade
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

* Update .pre-commit-config.yaml

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Marc Mueller <[email protected]>

Author: dependabot[bot]

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.20.0
+    rev: v2.21.0
     hooks:
       - id: pyupgrade
         args: [--py38-plus]

requirements.txt

@@ -1,5 +1,5 @@
 aiofiles==0.7.0
 autoflake==1.4
 isort==5.9.1
-pyupgrade==2.20.0
+pyupgrade==2.21.0
 reorder-python-imports==2.5.0

requirements_test_pre_commit.txt

@@ -1,3 +1,3 @@
 flake8==3.9.2
 isort==5.9.1
-pyupgrade==2.20.0
+pyupgrade==2.21.0