auparse: flush feed and release memory

This might produce some bad data if lines of data in input feed is incorrectly split

auditd-plugin-clickhouse.cpp

@@ -1020,6 +1020,10 @@ int main(int argc, char **argv)
 				if (readsize > 0)
 				{
 					auparse_feed(au.get(), data, readsize);
+
+					// assume that data wasn't split, and flush it
+					// otherwise, libauparse keeps increasing it's memory footprint
+					auparse_flush_feed(au.get());
 				}
 				else
 				{