Issue #3283 fix md5 timestamp with config force second run exception

[bdbaddog]

Fix issue #3283

- Fix Issue #3283 - Handle using --config=force in combination with Decider('MD5-timestamp').
  3.0.2 in fix for issue #2980 added that deciders can throw DeciderNeedsNode exception.
  The Configure logic directly calls the decider when using --config=force but wasn't handling
  that exception.  This would yield minimally configure tests using TryLink() not running and
  leaving TypeError Nonetype exception in config.log

Contributor Checklist:

• I have created a new test or updated the unit tests to cover the new/changed functionality.
• I have updated master/src/CHANGES.txt directory (and read the README.txt in that directory)
• I have updated the appropriate documentation

[codecov]

Codecov Report

Merging #3284 into master will decrease coverage by 0.01%.
The diff coverage is 75%.

@@            Coverage Diff             @@
##           master    #3284      +/-   ##
==========================================
- Coverage   87.78%   87.76%   -0.02%     
==========================================
  Files         187      187              
  Lines       24290    24296       +6     
==========================================
+ Hits        21323    21324       +1     
- Misses       2967     2972       +5

Impacted Files	Coverage Δ
src/engine/SCons/Job.py	93.88% <100%> (ø)	⬆️
src/engine/SCons/SConf.py	94.89% <71.42%> (-0.31%)	⬇️
src/engine/SCons/Util.py	80.62% <0%> (-0.35%)	⬇️

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