chore(deps): bump thiserror from 1.0.69 to 2.0.3 in /backend (#4738)

Bumps [thiserror](https://github.com/dtolnay/thiserror) from 1.0.69 to 2.0.3.
- [Release notes](https://github.com/dtolnay/thiserror/releases)
- [Commits](https://github.com/dtolnay/thiserror/compare/1.0.69...2.0.3)

---
updated-dependencies:
- dependency-name: thiserror
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

backend/Cargo.lock

@@ -10874,7 +10874,7 @@ dependencies = [
  "serde_json",
  "sha2 0.10.8",
  "sqlx",
- "thiserror 1.0.69",
+ "thiserror 2.0.3",
  "tikv-jemalloc-ctl",
  "tokio",
  "tracing",

backend/Cargo.toml

@@ -145,7 +145,7 @@ tower-cookies = "^0.10"
 serde = "^1"
 serde_json = { version = "^1", features = ["preserve_order", "raw_value"] }
 uuid = { version = "^1", features = ["serde", "v4"] }
-thiserror = "^1"
+thiserror = "^2"
 anyhow = "^1"
 chrono = { version = "0.4.35", features = ["serde"] }
 chrono-tz = "^0"