build(deps): bump gadget-sdk from 851c73f to 6b00641 (#71)

Bumps [gadget-sdk](https://github.com/webb-tools/gadget) from `851c73f` to `6b00641`.
- [Release notes](https://github.com/webb-tools/gadget/releases)
- [Commits](tangle-network/gadget@851c73f...6b00641)

---
updated-dependencies:
- dependency-name: gadget-sdk
  dependency-type: direct:production
...

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