Add value check to orgName in VSDashboardGate

[ameliav]

🗣 Description

Fix the edge case bug for undefined values for "Add an alert banner for Users a part of DHS Region 1-10 (CRASM-4000)"

💭 Motivation and context

Ensure alert banner will not error out for undefined/pre-loaded orgs. Continuation of #1509

🧪 Testing

See if an undefined or null org provides back an error

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All future TODOs are captured in issues, which are referenced in code comments.
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated to reflect the changes in this PR.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.
• Bump major, minor, patch, pre-release, and/or build versions as appropriate via the bump_version script if this repository is versioned and the changes in this PR warrant a version bump.
• Create a pre-release (necessary if and only if the pre-release version was bumped).

✅ Pre-merge checklist

• Revert dependencies to default branches.
• Finalize version.

✅ Post-merge checklist

• Create a release (necessary if and only if the version was bumped).

[jayjaybunce]

LGTM. Tested locally and bug has been squashed.

[hawkishpolicy]

tested locally.

works.