actions: Add destroy action

Add an action to destroy an object on signal match.

Change-Id: I23fb160bcf7507d0d0a5f2d82f1cfb24131adf76
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/manager.hpp b/manager.hpp
index 23d91da..5f78066 100644
--- a/manager.hpp
+++ b/manager.hpp
@@ -123,6 +123,9 @@
     /** @brief sd_bus signal callback. */
     void signal(sdbusplus::message::message &, auto &);
 
+    /** @brief Drop an object from DBus. */
+    void destroyObject(const char *);
+
     using Event = std::tuple<
         const char *,
         filters::details::Wrapper,