Update .github/workflows/pdf-release.yml

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Signed-off-by: James Ross <james@flyingrobots.dev>

Author: flyingrobots

.github/workflows/pdf-release.yml

@@ -27,7 +27,8 @@ jobs:
           os: debian
           args: -pdf -file-line-error -halt-on-error -interaction=nonstopmode -jobname=aion-WARP -output-directory=../pdf
         env:
-          TEXINPUTS: ..:.:
+        env:
+          TEXINPUTS: "..:.:"
 
       - name: Upload PDF artifact
         uses: actions/upload-artifact@v4