ci: run Nix checks on our own runner to avoid out of disk space (#482)

* ci: run Nix checks on our own runner to avoid out of disk space

* Fix

Author: danieldk

.github/workflows/nix_checks.yml

@@ -10,7 +10,8 @@ on:
 jobs:
   build:
     name: Nix checks
-    runs-on: ubuntu-latest
+    runs-on:
+      group: aws-highmemory-32-plus-nix
     steps:
       - uses: actions/checkout@v6
       - uses: DeterminateSystems/nix-installer-action@ef8a148080ab6020fd15196c2084a2eea5ff2d25