Update python-gnupg requirement from <=0.5.3,>=0.5 to >=0.5,<=0.5.4

Updates the requirements on [python-gnupg](https://github.com/vsajip/python-gnupg) to permit the latest version.
- [Release notes](https://github.com/vsajip/python-gnupg/releases)
- [Changelog](https://github.com/vsajip/python-gnupg/blob/master/release)
- [Commits](vsajip/python-gnupg@0.5.0...0.5.4)

---
updated-dependencies:
- dependency-name: python-gnupg
  dependency-type: direct:production
...

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

pyproject.toml

@@ -60,7 +60,7 @@ dependencies = [
   "pygtrie>=2.5,<=2.5.0",
   "psycopg[binary]>=3.1.8,<=3.2.3",
   "pyparsing>=3.1.0,<=3.2.1",
-  "python-gnupg>=0.5,<=0.5.3",
+  "python-gnupg>=0.5,<=0.5.4",
   "PyYAML>=5.1.1,<=6.0.2",
   "redis>=4.3,<5.2.2",
   "tablib<3.6.0",