Run bundle clean after bundle install

Running it beforehand was resulting in a corrupted state
if it was the first time bundle install was run.

jenkins/acceptance.sh

@@ -58,11 +58,12 @@ if [ -e $HOME/edx-rbenv_clean.tar.gz ]; then
     tar -C $HOME -xf $HOME/edx-rbenv_clean.tar.gz
 fi
 
-# Ensure the Ruby environment is in a clean state and
-# bootstrap Ruby requirements so we can run the tests
-bundle clean --force
+# Bootstrap Ruby requirements so we can run the tests
 bundle install
 
+# Ensure the Ruby environment contains no stray gems
+bundle clean --force
+
 # Reset the jenkins worker's virtualenv back to the
 # state it was in when the instance was spun up.
 if [ -e $HOME/edx-venv_clean.tar.gz ]; then

jenkins/all-tests.sh

@@ -66,11 +66,12 @@ if [ -e $HOME/edx-rbenv_clean.tar.gz ]; then
     tar -C $HOME -xf $HOME/edx-rbenv_clean.tar.gz
 fi
 
-# Ensure the Ruby environment is in a clean state and
-# bootstrap Ruby requirements so we can run the tests
-bundle clean --force
+# Bootstrap Ruby requirements so we can run the tests
 bundle install
 
+# Ensure the Ruby environment contains no stray gems
+bundle clean --force
+
 # Reset the jenkins worker's virtualenv back to the
 # state it was in when the instance was spun up.
 if [ -e $HOME/edx-venv_clean.tar.gz ]; then