[DEVOPS-1705] Fix US DEV Web CD

[joseph-flinn]

Type of change

- [ ] Bug fix
- [ ] New feature development
- [ ] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
- [ ] Build/deploy pipeline (DevOps)
- [ ] Other

Objective

Fix workflow dispatch inputs. Attached is a screenshot of a success dispatch to US DEV.

Code changes

• .github/workflows/build-web.yml: Explicitly set workflow dispatch inputs to strings

Screenshots

Before you submit

• Please add unit tests where it makes sense to do so (encouraged but not required)
• If this change requires a documentation update - notify the documentation team
• If this change has particular deployment requirements - notify the DevOps team
• Ensure that all UI additions follow WCAG AA requirements