Updated create_custom_subject to account for leap years as this was s… #1359

Job	Run time
Set CI/CD metadata	4s
Commit stage / Check file format	6s
Commit stage / Scan secrets	9s
Commit stage / Check Markdown format	5s
Commit stage / Check English usage	8s
Commit stage / Count lines of code	6s
Commit stage / Scan dependencies	23s
Test stage	0s
	1m 1s

Provide feedback