docker: Add cryptsetup package for LUKS testing

Add cryptsetup to the CI Docker image to enable LUKS encryption tests.
This is needed to create test images.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/docker/Dockerfile

@@ -69,6 +69,7 @@ RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
 	clang-18 \
 	coreutils \
 	cpio \
+	cryptsetup \
 	curl \
 	device-tree-compiler \
 	dosfstools \