Validate default bucket configuration on startup

[TimCsaky]

Description

ticket: https://apps.nrs.gov.bc.ca/int/jira/browse/SHOWCASE-3337
.. and some other changes required to make the default bucket feature optional.

• check default bucket doesnt also exist in database (prevents data integrity issues)
• simplify getBucket() function to always throw if no bucket found, update references to this function
• update github environment files with change of variables naming

Types of changes

Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the CONTRIBUTING doc
• I have checked that unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

[github-actions]

Coverage Report

Totals
Statements:	52.45% ( 2466 / 4702 )
Methods:	42.54% ( 268 / 630 )
Lines:	58.67% ( 1496 / 2550 )
Branches:	46.12% ( 702 / 1522 )

[codeclimate]

Code Climate has analyzed commit d5941ae and detected 2 issues on this pull request.

Here's the issue category breakdown:

Category	Count
Complexity	2

The test coverage on the diff in this pull request is 81.8% (50% is the threshold).

This pull request will bring the total coverage in the repository to 58.6% (0.1% change).

View more on Code Climate.

[jujaga]

It's looking pretty good at a semantic glance. As we are shaking some things up with the helm chart env values, we are going to need to bump the helm chart version so that these changes will actually catch on CI/CD on merge.