Patched tests for EOL dates for lambda runtimes

[chuckmeyer]

Issue #, if available:

Description of changes:
Some Lambda runtimes have moved from warning to errors for EOL. I've updated the tests to reflect this, but we may ultimately need a time sensitive way touch.

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[codecov]

Codecov Report

Merging #999 into master will increase coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #999      +/-   ##
==========================================
+ Coverage   86.73%   86.78%   +0.05%     
==========================================
  Files         133      133              
  Lines        7878     7878              
  Branches     1939     1939              
==========================================
+ Hits         6833     6837       +4     
- Misses        640      641       +1     
+ Partials      405      400       -5

Impacted Files	Coverage Δ
src/cfnlint/__init__.py	88.61% <0%> (ø)	⬆️
...ules/resources/properties/ListDuplicatesAllowed.py	98.36% <0%> (+1.63%)	⬆️
src/cfnlint/rules/parameters/Default.py	97.22% <0%> (+2.77%)	⬆️
src/cfnlint/rules/resources/properties/ImageId.py	85.71% <0%> (+3.57%)	⬆️

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[kddejong]

I think we should pin the dates for testing purposes.
self.collection.rules[0].current_date = datetime.datetime(2019, 6, 30) added to the setUp of the test rules so we can focus on that.