Bump pyyaml from 5.3.1 to 5.4

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 5.3.1 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](yaml/pyyaml@5.3.1...5.4)

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

Author: dependabot[bot]

requirements.txt

@@ -1,6 +1,6 @@
 grpcio-tools>=1.9.0,<=1.50.0
 grpcio>=1.9.0,<=1.50.0
-PyYAML==5.3.1
+PyYAML==5.4
 pytest>=7.0.0,<=7.1.3
 mock>=2.0.0
 pyqrllib>=1.2.3,<1.3.0