build(deps): bump the dart_dep group with 2 updates (#765)

Bumps the dart_dep group with 2 updates: [json_path](https://github.com/f3ath/jessie) and [math_expressions](https://github.com/fkleon/math-expressions).


Updates `json_path` from 0.7.6 to 0.8.0
- [Release notes](https://github.com/f3ath/jessie/releases)
- [Changelog](https://github.com/f3ath/jessie/blob/master/CHANGELOG.md)
- [Commits](f3ath/jessie@0.7.6...0.8.0)

Updates `math_expressions` from 3.0.0 to 3.1.0
- [Changelog](https://github.com/fkleon/math-expressions/blob/master/CHANGELOG.md)
- [Commits](fkleon/math-expressions@3.0.0...3.1.0)

---
updated-dependencies:
- dependency-name: json_path
  dependency-version: 0.8.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: dart_dep
- dependency-name: math_expressions
  dependency-version: 3.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: dart_dep
...

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

Author: dependabot[bot]

packages/langchain_community/pubspec.yaml

@@ -26,7 +26,7 @@ dependencies:
   flat_buffers: ^23.5.26
   glob: ^2.1.3
   http: ^1.4.0
-  json_path: ^0.7.6
+  json_path: ^0.8.0
   langchain_core: 0.3.9
   math_expressions: ^3.0.0
   meta: ^1.16.0