Bump protobuf from 3.15 to 3.18.3 in /source/tyr

Bumps [protobuf](https://github.com/protocolbuffers/protobuf) from 3.15 to 3.18.3.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/generate_changelog.py)
- [Commits](protocolbuffers/protobuf@v3.15.0...v3.18.3)

---
updated-dependencies:
- dependency-name: protobuf
  dependency-type: direct:production
...

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

source/tyr/requirements.txt

@@ -19,7 +19,7 @@ billiard==3.5.0.5 ; python_version < "3.9"
 configobj==5.0.6
 itsdangerous==1.1.0
 setuptools==44.1.0 ; python_version == "2.7"
-protobuf==3.15
+protobuf==3.18.3
 psycopg2 ; python_version < "3.9"
 psycopg2-binary ; python_version >= "3.9"
 pytz==2013.9