Refine ordered call test.

[redboltz]

If you just need ordered call for the same handler, you can use
MQTT_ORDERED(handler1, handler2, ...).
In this case, you need to call cleard_ordered() on the top of test.
It should be called before the each tests (tcp, tls, ws, wss).

If you need to call handler based on topological sorting, then you can
use chk.match("label1", handler1, "label2", handler2, ...).

[codecov]

Codecov Report

Merging #822 (5d502c4) into master (f161e38) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #822   +/-   ##
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  Coverage   82.73%   82.73%           
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  Files          62       62           
  Lines        8657     8657           
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  Hits         7162     7162           
  Misses       1495     1495