chore: update dev dependencies (#15)

Update the dev dependencies to the newest version so that the tests
pass again. This is an issue whenever there is a breaking release
of `ipld-core`. On the other hand it makes sure that we won't forget
to update `serde_ipld_dagcbor` and `serde_ipld_dagjson` to the latest
version of `ipld-core` after a release.

It also adds a CI job to make sure the checked-in Cargo.lock file is
up-to-date.

.github/workflows/ci.yml

@@ -77,3 +77,16 @@ jobs:
       - name: Build
         # `thumbv6m-none-eabi` can't be used as Serde doesn't compile there.
         run: cargo build --no-default-features --features serde
+
+  check-lockfile:
+    name: Make sure the lockfile is up-to-date
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Sources
+        uses: actions/checkout@v4
+
+      - name: Install Rust Toolchain
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Error if checked-in lockfile is not up-to-date
+        run: cargo build --locked

Cargo.toml

@@ -29,8 +29,8 @@ serde_bytes = { version = "0.11.5", default-features = false, optional = true }
 
 [dev-dependencies]
 serde_derive = "1.0.197"
-serde_ipld_dagcbor = "0.5.0"
-serde_ipld_dagjson = "0.1.2"
+serde_ipld_dagcbor = "0.6.0"
+serde_ipld_dagjson = "0.2.0"
 serde_json = "1.0.79"
 serde_test = "1.0.132"