libclat_test: use static libc++

shot in the dark fix for mainline T test failure:

libclat_test did not report any run:
CANNOT LINK EXECUTABLE "/data/local/tmp/libclat_test": cannot locate symbol "_ZTVNSt3__118basic_stringstreamIcNS_11char_traitsIcEENS_9allocatorIcEEEE" referenced by "/data/local/tmp/libclat_test"...

Bug: 398136085
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I10fea4441898a19430941ef4aa1951817cc350ba
diff --git a/service/native/libs/libclat/Android.bp b/service/native/libs/libclat/Android.bp
index 6c1c2c4..9554bd8 100644
--- a/service/native/libs/libclat/Android.bp
+++ b/service/native/libs/libclat/Android.bp
@@ -47,6 +47,7 @@
     srcs: [
         "clatutils_test.cpp",
     ],
+    stl: "libc++_static",
     header_libs: [
         "bpf_connectivity_headers",
     ],