Bump deps/json from a259ecc to 1b9a9d1

Bumps [deps/json](https://github.com/nlohmann/json) from `a259ecc` to `1b9a9d1`.
- [Release notes](https://github.com/nlohmann/json/releases)
- [Commits](nlohmann/json@a259ecc...1b9a9d1)

---
updated-dependencies:
- dependency-name: deps/json
  dependency-type: direct:production
...

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