adding file and lineno to "useless test"-message

[Idrinth]

I believe this should be sufficient to solve #1801
I would consider it to be a breaking change, since the output format changes, possibly making tools based on the current one unable to work.

[codecov-io]

Codecov Report

Merging #3198 into master will increase coverage by 0.14%.
The diff coverage is 78.94%.

@@             Coverage Diff              @@
##             master    #3198      +/-   ##
============================================
+ Coverage     82.23%   82.37%   +0.14%     
+ Complexity     3509     3507       -2     
============================================
  Files           140      140              
  Lines          9231     9231              
============================================
+ Hits           7591     7604      +13     
+ Misses         1640     1627      -13

Impacted Files	Coverage Δ	Complexity Δ
src/Framework/TestSuite.php	85.43% <77.61%> (+0.62%)	148 <0> (-3)	⬇️
src/Framework/TestResult.php	75.38% <88.88%> (+2.63%)	164 <0> (+1)	⬆️
src/Framework/TestFailure.php	83.78% <0%> (+2.7%)	19% <0%> (ø)	⬇️

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