Update data directory path and version to v3.5

Pull Request Testing

[x] Describe testing already performed for these changes:
None.
[x] Recommend testing for the reviewer(s) to perform:
For multiple reviewers, list specific instructions for each:
@JohnHalleyGotway - Not sure if this can be tested as-is now. Should work ok? But need to download data fresh from Mohawk since that directory structure changed.
Will need to retag v3.5 after this is committed.
[x] Are any changes to the online tutorial required for this PR? [No]
If yes, please describe:
Changes already made online.
[x] Will this PR change the output of any of the existing cases? [Yes]
If yes, please describe:
This script is updated to version v3.5 which includes changes to plots, model versions, etc.
[x] Please complete this pull request review by [9/29/2021].

[ ] Ensure the PR title matches the feature or bugfix branch name. - Oops, sorry!
[x] Define the PR metadata, as permissions allow: Select: Reviewer(s), Projects(s), and Milestone.
[x] After submitting the PR, select Linked issues with the original issue number.
[x] After the PR is approved, merge your changes, as permissions allow.
[ ] Close the linked issue and delete your feature or bugfix branch from GitHub.