buildkite: run kani if devctr is modified

rebuilding the docker container can upgrade kani, and we'd like to know
at the PR stage if that causes issues (such as timeouts).

(cherry picked from commit 0fff2c8)
Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

.buildkite/pipeline_pr.py

@@ -51,6 +51,7 @@
 if not pipeline.args.no_kani and (
     not changed_files
     or any(x.suffix in [".rs", ".toml", ".lock"] for x in changed_files)
+    or any(x.parent.name == "devctr" for x in changed_files)
 ):
     kani_grp = pipeline.build_group(
         "🔍 Kani",