Does your product owner or customer care about these warnings? If no, my vote as a team member would be not to include them in the Product Backlog. Your team - your choice.
I'd like to expand on my preference as a team member.
What you're describing isn't necessarily what I would call debt, but instead undesirable technical behavior. It's a semantic difference, but somewhat important IMO. Technical debt is something that inhibits your ability to deliver new value to your PO.
You don't know what decisions you make today in good faith will slow you in the future. For that reason, technical debt is something you will always have and should be solving in the context of new value. This is why I would likely not put it on the backlog, but as new value PBIs came along I would solve my Technical Debt in the context of those PBIs. This aligns with Ian's and Sanjay's responses I believe.
Again, if your team were to choose to put them on the PB... I'm ok with that. But treat that choice as an experiment like any other retrospective outcome and inspect on it's impact to your PO, grooming, etc.