Merge pull request #265 from NHSDigital/dependabot/pip/black-26.3.1

Bump black from 25.1.0 to 26.3.1

Author: sathiya-nhs

poetry.lock

@@ -32,7 +32,7 @@ authlib = "1.6.6"
 
 [tool.poetry.group.dev.dependencies] 
 flake8 = "^7.3.0"
-black = "^25.1.0"
+black = "^26.3.1"
 pip-licenses = "^5.0.0"
 jinja2 = "^3.1.6"
 pytest = "^8.3.5"