Update build.sh

Testing upgrade option

Author: brianjo

.jenkins/build.sh

@@ -13,7 +13,7 @@ sudo apt-get install -y --no-install-recommends unzip p7zip-full sox libsox-dev
 
 export PATH=/opt/conda/bin:$PATH
 rm -rf src
-pip install -r $DIR/../requirements.txt
+pip install -r -U $DIR/../requirements.txt
 
 # export PATH=/opt/conda/bin:$PATH
 # pip install sphinx==1.8.2 pandas