ci: ensure builds are reproducible

Change-Id: I62741af7106d410f161708990b309c886ec4a7c6
diff --git a/.github/workflows/linkcheck.yml b/.github/workflows/linkcheck.yml
index 4af48ec..71cb868 100644
--- a/.github/workflows/linkcheck.yml
+++ b/.github/workflows/linkcheck.yml
@@ -6,11 +6,14 @@
 
 permissions: {}
 
+env:
+  SPHINXOPTS: --color
+
 jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - name: Checkout
+      - name: Checkout repository
         uses: actions/checkout@v3
       - name: Set up Python
         uses: actions/setup-python@v4
@@ -22,5 +25,3 @@
           pip install -r requirements.txt
       - name: Check external links
         run: make linkcheck
-        env:
-          SPHINXOPTS: --color