fix(deps): bump tonlibjson-sys/ton from 1b7c46f to 2a68c86

Bumps [tonlibjson-sys/ton](https://github.com/ton-blockchain/ton) from `1b7c46f` to `2a68c86`.
- [Release notes](https://github.com/ton-blockchain/ton/releases)
- [Commits](ton-blockchain/ton@1b7c46f...2a68c86)

---
updated-dependencies:
- dependency-name: tonlibjson-sys/ton
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>