[SYCL][E2E] Fix preview testing of vec_rel_swizzle_ops (#12040)

The commit introducing vec_rel_swizzle_ops missed testing with the
preview options due to a fix happening in the interrim. It is supposed
to build with the %{build} tag to ensure CUDA and HIP are built with the
correct target binaries. This commit fixes this issue.

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

sycl/test-e2e/Regression/vec_rel_swizzle_ops.cpp

@@ -1,7 +1,7 @@
 // RUN: %{build} -o %t.out
 // RUN: %{run} %t.out
 
-// RUN: %if preview-breaking-changes-supported %{ %clangxx -fsycl -fpreview-breaking-changes %s -o %t2.out %}
+// RUN: %if preview-breaking-changes-supported %{ %{build} -fpreview-breaking-changes -o %t2.out %}
 // RUN: %if preview-breaking-changes-supported %{ %{run} %t2.out %}
 
 #include <cstdlib>