[Feature] Privacy disclaimer in Resume Upload

**Describe new addition**
The resume upload functionality in the ACM Portal is really neat, though I immediately was asking myself how that resume will be used. It would make me feel more confident in using it if there was a short explainer about how the resume will be used (Ex: Shared with sponsors, used in applications, etc).

**Task List**
- [ ] Verify uses for resumes in ACM
- [ ] Insert explainer text on Upload Resume section

Search the codebase for the "Upload Resume" area and locate the page/component that renders that section. Read nearby resume upload handling to confirm how resumes are currently used and shared so the new disclaimer text is accurate. The issue names no specific files or tests, so done means the resume upload screen now displays the explainer text in the right section.

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