[contrib] Stop building ICU tools to fix gcc Envoy build

Clang and gcc are subtly different and it seems to be the cause
of contrib build failures reported in
envoyproxy#31807 (e.g., when using
gcc to link the final binary it results in a bunch of essential
for gcc C++ symbols like __gxx_personality_v0).

The issue appear to be the order of the libraries when linking.
gcc, when building statically linked binaries basically needs
libstdc++ to be the last library or alsmot the last library in
the command line. And clang does not appear to care about it
much.

This change provides libstdc++ library in LIBS environment variabe
which will put it in the right position when building the ICU
library. This works well for both clang and gcc.

Signed-off-by: Mikhail Krinkin <[email protected]>

bazel/foreign_cc/BUILD

@@ -199,6 +199,7 @@ configure_make(
     env = {
         "CXXFLAGS": "-fPIC -DU_CHARSET_IS_UTF8=1 -DU_USING_ICU_NAMESPACE=0 -DUCONFIG_ONLY_HTML_CONVERSION=1 -DUCONFIG_NO_LEGACY_CONVERSION=1 -DUCONFIG_NO_BREAK_ITERATION=1 -DUCONFIG_NO_COLLATION=1 -DUCONFIG_NO_FORMATTING=1 -DUCONFIG_NO_TRANSLITERATION=1 -DUCONFIG_NO_REGULAR_EXPRESSIONS=1",
         "CFLAGS": "-fPIC",
+        "LIBS": "-l:libstdc++.a",
         "ICU_DATA_FILTER_FILE": "$(execpath //bazel/foreign_cc:icu_data_filter.json)",
     },
     lib_source = "@com_github_unicode_org_icu//:all",