Add default time sync object path

The time sync object path is empty by default and is initialized by a
dbus call at runtime.
It works OK in BMC but the unit tests in the repo is broken due to the
empty string used in the sdbus matcht_t.

Add a config option to initialize the default time sync object path, so
that it works both on BMC and in unit tests.

Signed-off-by: Lei YU <yulei.sh@bytedance.com>
Change-Id: Iccdaef58434a1227c4ea73230ba23b4e618a2d2d
diff --git a/.clang-tidy b/.clang-tidy
index de69285..5fca7ce 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -303,7 +303,7 @@
 readability-uppercase-literal-suffix'
 
 WarningsAsErrors: '*'
-HeaderFilterRegex: '.*'
+HeaderFilterRegex: '.*.hpp'
 
 CheckOptions:
   - { key: readability-identifier-naming.ClassCase,     value: CamelCase  }