Bump src/external/gsl from 3325bbd to 7e0943d (#79)

Bumps [src/external/gsl](https://github.com/microsoft/GSL) from `3325bbd` to `7e0943d`.
- [Release notes](https://github.com/microsoft/GSL/releases)
- [Commits](microsoft/GSL@3325bbd...7e0943d)

---
updated-dependencies:
- dependency-name: src/external/gsl
  dependency-version: 7e0943d20d3082b4f350a7e0c3088d2388e934de
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]