Merge pull request #140 from sagemath/ci/conda-yes-2

Add -y flag to conda create as well

Author: embray

.travis.yml

@@ -37,7 +37,7 @@ install:
       conda config --set show_channel_urls true
       conda info
 
-    - conda create --name test python=${PYTHON_VERSION}
+    - conda create -y --name test python=${PYTHON_VERSION}
     - conda activate test
     # We need the toolchain stuff to work around
     # https://github.com/conda/conda/issues/6030