Fix: PityUnit make resilient against cwd changes.

src/AbstractPityUnit.cc

@@ -15,7 +15,7 @@
 namespace pEp {
     namespace PityTest11 {
         // static
-        std::string AbstractPityUnit::_global_root_dir = "./pitytest_data/";
+        std::string AbstractPityUnit::_global_root_dir = Utils::path_get_abs("pitytest_data/");
         // static
         bool AbstractPityUnit::debug_log_enabled = false;
         // static