CI: fix path to target dir (#361)

Author: newAM

.github/workflows/ci.yml

@@ -199,7 +199,7 @@ jobs:
           cargo +nightly rustdoc \
           --features chrono,embedded-time,rt,stm32wl5x_cm4 \
           -- -Z unstable-options --enable-index-page
-          chmod -R 777 target
+          chmod -R 777 ../target
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v2
         with: