Bump lib/spm_2_bids from 66aaed8 to bec6ef8 (#1252)

Bumps [lib/spm_2_bids](https://github.com/cpp-lln-lab/spm_2_bids) from `66aaed8` to `bec6ef8`.
- [Release notes](https://github.com/cpp-lln-lab/spm_2_bids/releases)
- [Commits](cpp-lln-lab/spm_2_bids@66aaed8...bec6ef8)

---
updated-dependencies:
- dependency-name: lib/spm_2_bids
  dependency-type: direct:production
...

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

Author: dependabot[bot]