Addressed a Typo in IRC validation

[nateharms]

In RMG 2.4, creating a RMG molecule from smiles would look like this Molecule(SMILES='smiles_string'). However, when RMG was updated to python 3 the naming convention changed to Molecule(smiles='smiles_string'). This PR addresses this for validation of IRCs.

[codecov]

Codecov Report

Merging #52 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master      #52   +/-   ##
=======================================
  Coverage   63.25%   63.25%           
=======================================
  Files          27       27           
  Lines        4629     4629           
=======================================
  Hits         2928     2928           
  Misses       1701     1701

Impacted Files	Coverage Δ
autotst/calculator/gaussian.py	63.37% <0%> (ø)	⬆️

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[davidfarinajr]

Looks good!

[nateharms]

The only issue at the moment is the the patch doesn't hit the target coverage. This is because these lines of code weren't tested before. A todo should be to add tests to this in the future. See issue #55). Will take care of this soon.