TSPS-404 Throw correct exception for Sam user not found

[mmorgantaylor]

Teaspoons uses TCL's SamUserFactory to check that the user is registered in Sam.

However, if a user is not registered in Sam/Terra, TCL is currently throwing an InternalServerErrorException that results in a 500 response, with the error message stating that the user was not found in Sam and an error code of 403 (FORBIDDEN). That's because TCL expects Sam to return a 404 (NOT_FOUND), so it doesn't properly handle the 403 that Sam returns in this case .

This PR updates the logic so that TCL treats both a 404 and a 403 as "User not found".

Teaspoons Jira ticket: https://broadworkbench.atlassian.net/browse/TSPS-404

[sonarqubecloud]

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 SonarQube Cloud

[pshapiro4broad]

This seems correct with respect to Sam's behavior, but I wonder why 403/forbidden is being returned instead of 404/not found in the first place? I would expect a 404 if a user isn't found.

[mmorgantaylor]

after some discussion offline, I'll move ahead with this PR. there are reasons Sam returns a 403 and reasons that this is remapped to a 401 that are beyond the scope of this PR to reconsider.