Describe the bug
OMP will either display the catalog.forthcoming or catalog.published message on the monograph landing page, depending on the publication date of a monograph. This message is chosen based on:

https://github.com/pkp/omp/blob/stable-3_3_0/templates/frontend/objects/monograph_full.tpl#L406

but this test will fail and display Forthcoming in cases when it should not, if the Date Format in Website Settings is something other than the default. In the screenshot below, choosing the circled format results in a Forthcoming message for a monograph with a publication date in 2022. Setting it back to the default as chosen fixes the issue.

Seen in 3.3 but probably also in 3.4

Suggest converting these to time stamps instead, to make the math consistent.