Set SITE_DIR from a step since the runner context is unavailable in job-level env

Author: rartino

.github/workflows/docs-release.yml

@@ -14,9 +14,10 @@ concurrency:
 jobs:
   build:
     runs-on: ubuntu-latest
-    env:
-      SITE_DIR: ${{ runner.temp }}/httk-docs-site
     steps:
+      - name: Resolve the site staging directory
+        run: echo "SITE_DIR=$RUNNER_TEMP/httk-docs-site" >> "$GITHUB_ENV"
+
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0

.github/workflows/docs-repair.yml

@@ -19,9 +19,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     environment: docs-repair
-    env:
-      SITE_DIR: ${{ runner.temp }}/httk-docs-site
     steps:
+      - name: Resolve the site staging directory
+        run: echo "SITE_DIR=$RUNNER_TEMP/httk-docs-site" >> "$GITHUB_ENV"
+
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0

.github/workflows/docs.yml

@@ -15,9 +15,10 @@ concurrency:
 jobs:
   build:
     runs-on: ubuntu-latest
-    env:
-      SITE_DIR: ${{ runner.temp }}/httk-docs-site
     steps:
+      - name: Resolve the site staging directory
+        run: echo "SITE_DIR=$RUNNER_TEMP/httk-docs-site" >> "$GITHUB_ENV"
+
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0