[CI] Run the `codespell` tool to find common spelling mistakes

.gitlab-ci.yml

@@ -58,3 +58,10 @@ system-test:
     branch: core
     strategy: depend
   allow_failure: true
+
+# Check for spelling mistakes in text
+code-spelling-check:
+  stage: .pre
+  image: registry.dune-project.org/docker/ci/debian:11
+  script:
+  - codespell

CHANGELOG.md

@@ -61,6 +61,8 @@ In order to build the DUNE core modules you need at least the following software
 
 - Deprecate cmake function `remove_processed_modules`
 
+- The CI system now checks for common spelling mistakes using the `codespell` tool.
+
 ## Deprecations and removals
 
 - Helper fallback implementations for `Std::to_false_type`, `Std::to_true_type`,