Update dependency architect to v5.15.0 (#252)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.circleci/config.yml

@@ -1,6 +1,6 @@
 version: 2.1
 orbs:
-  architect: giantswarm/architect@5.14.0
+  architect: giantswarm/architect@5.15.0
 
 jobs:
   unit-tests: