Update make-pdf-1-select.yml

.github/workflows/make-pdf-1-select.yml

@@ -17,7 +17,7 @@ jobs:
         run: |
           echo "selected PDF: ${{ github.event.inputs.pdf_target }}"
 
-      - name: Print start date
+      - name: print start date
         run: date +%Y-%m-%d_%H:%M
 
       - name: Checkout repository
@@ -26,6 +26,19 @@ jobs:
           persist-credentials: false
           fetch-depth: 1 # 0 if you want to push to repo
 
+      - name: caching LaTeX files
+        uses: actions/cache@v4
+        with:
+          path: |
+            chapters/*.aux
+            hpmor*.aux
+            hpmor*.pdf
+            hpmor*.xdv
+          key: tex-cache
+
+      - name: ls chapters
+        run: ls -l chapters/
+
       - name: Python set up
         uses: actions/setup-python@v5
         with: