Attempt to fix Coq CI

Coq CI is broken since a few days because it compiles the wrong version of iris, obtained from the OPAM file here in iris-example. Merging this should fix it.

I am fine bumping the version of Iris regardless, so merging.

To be clear: The Coq CI failure is due to iris@026c3af0 I presume?

enabled an automatic merge when the pipeline for c39b6834 succeeds

merged

mentioned in commit 71116369

Thanks!