Disable jit on msan job

JIT code is not instrumented and as such incompatible with msan.
I'm not sure why this only started failing in the last build, it
shouldn't have worked before either...

Author: nikic

azure/msan_job.yml

@@ -31,6 +31,7 @@ jobs:
             --disable-xmlreader \
             --disable-xmlwriter \
             --without-pcre-jit \
+            --disable-opcache-jit \
             --enable-phpdbg \
             --enable-fpm \
             --with-pdo-mysql=mysqlnd \