fix: Fixed the job submission example

[evanspearman-a]

What was the problem/requirement? (What/Why)

examples/submit_job.py was failing because:

1. The job attachments API had changed since the example was written
2. The example was assuming credentials existed in the environment
3. The job template was formatted incorrectly

What was the solution? (How)

1. Update the calls to job attachments to use the new API
2. Switch to using deadline client's API for getting a boto3 session
3. Fix the format of the job template

What is the impact of this change?

The job submission example now works

Fixes #408

How was this change tested?

I submitted the job to a queue and observed that the job succeeded and had the correct output:

Confirming that inputs were downloaded to the correct location
2024/07/22 16:30:59-05:00 Total number of inputs
2024/07/22 16:30:59-05:00 1
2024/07/22 16:30:59-05:00 Total file size
2024/07/22 16:30:59-05:00 4.0K	/sessions/session-49cc07f051fa4a60b16fb3c1839488eb323fbt0g/assetroot-835c71fd6af6a5fe1ac2
2024/07/22 16:30:59-05:00 Creating the expected output directory and output file

Was this change documented?

N/A

Is this a breaking change?

No

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud