test-channel-introspect: remove most MYASSERTs
test-channel-introspect: remove most MYASSERTs

This macro is really ugly. I only left it in place for assertions like

  MYASSERT (!tp_proxy_prepare_finish (chan, prepare_result, &error), "");

where the assertion has a side-effect. Otherwise, if someone disables
assertions the test will crash. Ugh.

Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib,Distrotech/telepathy-glib