Disable a warning for asan compile.

When running gcc12, asan throws out a maybe-uninitialized
warning in some gcc-internal regexp headers. Let's disable.

Signed-off-by: Henner Zeller <hzeller@google.com>

.github/bin/build-and-test.sh

diff --git a/.github/bin/build-and-test.sh b/.github/bin/build-and-test.sh
index 7ab9ec1..f059ac7 100755
--- a/.github/bin/build-and-test.sh
+++ b/.github/bin/build-and-test.sh
@@ -83,6 +83,10 @@
     ;;
 
   asan|asan-clang)
+    if [[ "${MODE}" == "asan" ]]; then
+      # Some gcc 12 issue with regexp it seems.
+      BAZEL_OPTS="${BAZEL_OPTS} --cxxopt=-Wno-maybe-uninitialized"
+    fi
     bazel test --config=asan --cache_test_results=no --test_output=errors $BAZEL_OPTS -c fastbuild ${CHOSEN_TARGETS}
     ;;