[Publisher][Superagencies] Add dropdown for child agencies

[nasaownsky]

Description of the change

New PR with fixed superagency id getting method and dropdown added to Explore Data page.

Type of change

All pull requests must have at least one of the following labels applied (otherwise the PR will fail):

Label	Description
Type: Bug	non-breaking change that fixes an issue
Type: Feature	non-breaking change that adds functionality
Type: Breaking Change	fix or feature that would cause existing functionality to not work as expected
Type: Non-breaking refactor	change addresses some tech debt item or prepares for a later change, but does not change functionality
Type: Configuration Change	adjusts configuration to achieve some end related to functionality, development, performance, or security
Type: Dependency Upgrade	upgrades a project dependency - these changes are not included in release notes

Related issues

closes #1275 closes #1276

Checklists

Development

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• [ ] Tests have been written to cover the code changed/added as part of this pull request

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[nasaownsky]

Hi @mxosman! Sorry for this issue, it was totally on my end!

New getting method for superagency id should work as expected. I've also added dropdown in Explore Data page in this PR. Could you please test it with multiple superagencies to verify that this working properly?

[nasaownsky]

@mxosman please check my fixes!

[nasaownsky]

@mxosman Oh, great catches, thank you!