In Step 7, default license for code should be MIT

[DerekMolnar]

Describe the bug
Currently, Creative Commons Attribution 4.0 Commons license is defaulted for Software code. Instead, the MIT License should be defaulted.

Is this a regression?
No.

Steps to Reproduce

1. Go to Step 3 and add a data set with a datatype of "source code"
2. In Step 7 see that this data set has been defaulted with the CC BY license

Expected behavior
The MIT license should be defaulted for data sets marked as "source code"

Screenshots

[DerekMolnar]

@ChristianeStork please add/edit as needed

[ChristianeStork]

Perfect description, nothing to add. Thanks!