Bump Features/DFCI from 3e7a25b to a620f74

Bumps [Features/DFCI](https://github.com/microsoft/mu_feature_dfci) from `3e7a25b` to `a620f74`.
- [Release notes](https://github.com/microsoft/mu_feature_dfci/releases)
- [Commits](microsoft/mu_feature_dfci@3e7a25b...a620f74)

---
updated-dependencies:
- dependency-name: Features/DFCI
  dependency-type: direct:production
...

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