Bump kudobuilder/kuttl in /images/scorecard-test-kuttl

Bumps kudobuilder/kuttl from v0.9.0 to v0.15.0.

---
updated-dependencies:
- dependency-name: kudobuilder/kuttl
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

images/scorecard-test-kuttl/Dockerfile

@@ -18,7 +18,7 @@ RUN GOOS=linux GOARCH=$TARGETARCH make build/scorecard-test-kuttl
 
 # Final image.
 #FROM kudobuilder/kuttl@sha256:924a709a1d2c6bede8815415ea5d5be640b506ec5aeaddc68acb443ae8ee7926
-FROM kudobuilder/kuttl:v0.9.0
+FROM kudobuilder/kuttl:v0.15.0
 
 ENV HOME=/opt/scorecard-test-kuttl \
     USER_NAME=scorecard-test-kuttl \