[circleci] Disable msan and ubsan builds

https://github.com/harfbuzz/harfbuzz/issues/1174
https://github.com/harfbuzz/harfbuzz/issues/1175

.circleci/config.yml

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 671f49d..7baebb1 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -249,9 +249,9 @@
       - archlinux-debug-O0-py3
       - clang-O3-O0
       - clang-asan
-      - clang-msan
+      #- clang-msan
       - clang-tsan
-      - clang-ubsan
+      #- clang-ubsan
       - fedora-outoftreebuild
 
       # cmake based builds