Ci docs (#15)

* Remove cache during docker build

* Add some docs for Prow

ci/Dockerfile

@@ -14,11 +14,13 @@ RUN yum install -y \
       python3-devel \
       python3-pip \
       python3-setuptools \
- && pip3 install --upgrade setuptools pip \
- && pip3 install \
+ && pip3 install --no-cache-dir --upgrade setuptools pip \
+ && pip3 install --no-cache-dir \
       openshift \
       ansible \
-      molecule
+      molecule \
+  && yum clean all \
+  && rm -rf $HOME/.cache
 
 COPY . /opt/ansible
 

ci/incluster_integration.sh

@@ -2,7 +2,7 @@
 
 set -x
 
-# IMAGE_FORMAT be in the form $registry/$org/$image:$$component, ie
+# IMAGE_FORMAT is in the form $registry/$org/$image:$$component, ie
 # quay.io/openshift/release:$component
 # To test with your own image, build and push the test image
 # (using the Dockerfile in ci/Dockerfile)