Fix Local Mode for non Framework containers.

[iquintero]

Don't assume that sagemaker_submit_directory is present in the
hyperparameters.

Issue #, if available:

Description of changes:

Merge Checklist

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[nadiaya]

Needs an integ (or unit).
Talked offline - Nacho is adding it.

[codecov-io]

Codecov Report

Merging #213 into master will decrease coverage by 0.06%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #213      +/-   ##
==========================================
- Coverage   91.55%   91.49%   -0.07%     
==========================================
  Files          45       45              
  Lines        3162     3163       +1     
==========================================
- Hits         2895     2894       -1     
- Misses        267      269       +2

Impacted Files	Coverage Δ
src/sagemaker/local/image.py	85.48% <100%> (-0.59%)	⬇️

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