This is the documentation for ConfiForms Server/Data Center appHowever, this might also work for ConfiForms cloud and in most cases it does. But please see this page to understand the differences between server and cloud versions of the ConfiForms app.
Confluence editor is very restricted around URLs (links) and for dynamically constructed URLs you might have in your IFTTT macro body it might just remove them.
To workaround the issue you will need to put an HTML macro that wraps the link in HTML format. This way you will ensure that the link is stored in the same format as you wanted