If the mail contains "BIOPROD MANAGER APPROVAL" this as subject and you wish to click on this link, then do one thing.
I think the whole mails will be displayed in webtable. Add that webtable and retrieve the subject cell value and verify the cell value. It it matches click on the cell value.
I think the whole mails will be displayed in webtable. Add that webtable and retrieve the subject cell value and verify the cell value. It it matches click on the cell value.