Bump protobuf from 3.19.4 to 4.21.2

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 3.19.4 to 4.21.2.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/generate_changelog.py)
- [Commits](https://github.com/protocolbuffers/protobuf/commits)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements.in

@@ -4,7 +4,7 @@ cffi==1.15.0
 future==0.18.2
 itsdangerous==2.0.1
 pbr==1.10.0
-protobuf==3.19.4
+protobuf==4.21.2
 pyopenssl==19.1.0
 PyYAML==5.2 # PyYAML 5.3 does not support Python 3.4
 pytz==2021.3

requirements.txt

@@ -30,7 +30,7 @@ itsdangerous==2.0.1
     # via -r requirements.in
 pbr==1.10.0
     # via -r requirements.in
-protobuf==3.19.4
+protobuf==4.21.2
     # via -r requirements.in
 pycparser==2.18
     # via cffi

setup.py

@@ -20,7 +20,7 @@
     install_requires=[
         "deprecated==1.2.13",
         "cryptography>=2.2.1",
-        "protobuf==3.13.0",
+        "protobuf==4.21.2",
         "requests>=2.11.1",
         "future>=0.18.2",
         "asn1==2.2.0",
@@ -35,7 +35,7 @@
             "Flask>=1.0.4",
             "python-dotenv>=0.7.1",
             "django-sslserver>=0.22.0",
-            "Werkzeug==2.0.2",
+            "Werkzeug==2.1.2",
         ],
         "dev": [
             "pre-commit==2.16.0",
@@ -46,9 +46,9 @@
             "python-coveralls==2.9.3",
             "coverage==4.5.4",
             "mock==2.0.0",
-            "virtualenv==20.13.0",
+            "virtualenv==20.14.1",
             "flake8==4.0.1",
-            "pip-tools==6.4.0",
+            "pip-tools==6.6.2",
         ],
     },
     classifiers=[