ci(dependabot): ignore canary prereleases

Dependabot proposed a commit-hash canary build because "canary" sorts
after "beta" in semver prerelease ordering. Canary builds are nightly
snapshots published under their own dist-tag, not releases, so they
are never a valid upgrade target for a pinned dependency.

Both midnight scopes are in use, so both are covered.

Author: 0xisk

.github/dependabot.yml

@@ -6,6 +6,13 @@ updates:
       interval: "daily"
     open-pull-requests-limit: 5
     rebase-strategy: "auto"
+    ignore:
+      # Nightly canary snapshots are not releases, but "canary" sorts after
+      # "beta", so Dependabot would otherwise propose them.
+      - dependency-name: "@midnight-ntwrk/*"
+        versions: ["*-canary*"]
+      - dependency-name: "@midnightntwrk/*"
+        versions: ["*-canary*"]
 
   - package-ecosystem: "github-actions"
     directory: "/"