Remove Kani temp files from book upload (rust-lang#1793)

When Kani crashes or timeout, it leaves behind all the temporary files.
While running the bookrunner, that can happen because of some
instability or timeout. Thus, we need to manually delete these files for
now to avoid uploading them as part of the bookrunner artifacts.

scripts/build-docs.sh

@@ -36,6 +36,9 @@ if [ -d $HTML_DIR ]; then
     # Replace artifacts by examples under test
     BOOKS_DIR=$KANI_DIR/tests/bookrunner/books
     rm -r src/bookrunner/artifacts
+    # Remove any json files that Kani might've left behind due to crash or timeout.
+    find $BOOKS_DIR -name '*.json' -exec rm {} \;
+    find $BOOKS_DIR -name '*.out' -exec rm {} \;
     cp -r $BOOKS_DIR src/bookrunner/artifacts
     # Update paths in HTML report
     python $KANI_DIR/scripts/ci/update_bookrunner_report.py src/bookrunner/index.html new_index.html