workflows/check-format: add actionlint

I added a lint-action.sh script in .github/workflows a while ago while
fixing some warnings. But I haven't run it myself ever since. This needs
to be part of CI to make any use of it.

.github/workflows/eval.yml

@@ -219,7 +219,7 @@ jobs:
           # Use the target branch to get accurate maintainer info
           nix-build target/ci -A eval.compare \
             --arg beforeResultDir ./targetResult \
-            --arg afterResultDir $(realpath prResult) \
+            --arg afterResultDir "$(realpath prResult)" \
             --arg touchedFilesJson ./touched-files.json \
             -o comparison
 

.github/workflows/lint-actions.sh

@@ -1,7 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash actionlint shellcheck -I nixpkgs=../..
-set -euo pipefail
-
-SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
-cd "$SCRIPT_DIR/../.."
-actionlint

ci/default.nix

@@ -44,6 +44,8 @@ let
         # By default it's info, which is too noisy since we have many unmatched files
         settings.on-unmatched = "debug";
 
+        programs.actionlint.enable = true;
+
         programs.keep-sorted.enable = true;
 
         # This uses nixfmt-rfc-style underneath,