ci: Use nightly blueprint-compiler

The current version of blueprint-compiler used to compile is different from
the version used to run the format check. This means that running the formatter
locally does not get the format check passing.

This commit changes the format check from getting the blueprint-compiler from
the latest Fedora image to getting it from the GNOME OS OCI nightly image,
ensuring that it is always up-to-date.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-calendar/-/merge_requests/736>

.gitlab-ci.yml

@@ -35,10 +35,9 @@ style-check-diff:
   allow_failure: true
 
 blueprint-format:
-  image: fedora:latest
+  image: quay.io/gnome_infrastructure/gnome-build-meta:core-nightly
   stage: check
   before_script:
-    - dnf install -y blueprint-compiler
     - shopt -s globstar
   script:
     - blueprint-compiler format **/*.blp