also build nightly against known-to-work Coq version

.gitlab-ci.yml

@@ -58,7 +58,19 @@ build-coq.8.8.2:
   variables:
     OPAM_PINS: "coq version 8.8.2"
 
-build-stdpp.dev:
+# Nightly job with a known-to-work Coq version
+build-stdpp.dev-coq.8.11.0:
+  <<: *template
+  variables:
+    OPAM_PINS: "coq version 8.11.0   coq-stdpp.dev git git+https://gitlab.mpi-sws.org/iris/stdpp.git#$STDPP_REV"
+  except:
+  only:
+  - triggers
+  - schedules
+  - api
+
+# Nightly job with Coq master
+build-stdpp.dev-coq.dev:
   <<: *template
   variables:
     OPAM_PINS: "coq version dev   coq-stdpp.dev git git+https://gitlab.mpi-sws.org/iris/stdpp.git#$STDPP_REV"