travis: don't explode html docs

It turns out that cleaning up these files on jfrog is a very time consuming process, even with the help of scripts.

Author: dlech

.travis.yml

@@ -91,8 +91,7 @@ jobs:
           pybricks-ev3dev/$TRAVIS_REPO_SLUG/build$TRAVIS_JOB_NUMBER/
         - tar -C ${HOME}/micropython/ports/pybricks/doc/build html -czf html.tar.gz
         - jfrog rt upload --build-name $TRAVIS_REPO_SLUG --build-number $TRAVIS_JOB_NUMBER
-          --explode=true "html.tar.gz"
-          pybricks-ev3dev/$TRAVIS_REPO_SLUG/build$TRAVIS_JOB_NUMBER/
+          "html.tar.gz" pybricks-ev3dev/$TRAVIS_REPO_SLUG/build$TRAVIS_JOB_NUMBER/
         - jfrog rt upload --build-name $TRAVIS_REPO_SLUG --build-number $TRAVIS_JOB_NUMBER
           --props "pypi.name=fake-pybricks;pypi.version=$FAKE_PYBRICKS_VERSION"
           "${HOME}/micropython/ports/pybricks/lib/fake-pybricks/dist/fake-pybricks-$FAKE_PYBRICKS_VERSION.tar.gz"