Improve Provider tests

[mthenw]

Just some improvements in provider tests.

[codecov-io]

Codecov Report

Merging #397 into master will increase coverage by 2.37%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #397      +/-   ##
==========================================
+ Coverage   56.55%   58.92%   +2.37%     
==========================================
  Files          24       24              
  Lines        1434     1434              
==========================================
+ Hits          811      845      +34     
+ Misses        577      546      -31     
+ Partials       46       43       -3

Impacted Files	Coverage Δ
providers/awskinesis/awskinesis.go	79.54% <0%> (+29.54%)	⬆️
providers/awslambda/awslambda.go	82.35% <0%> (+41.17%)	⬆️

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