Cleanup executor specific requirements

Ara and openstacksdk are installed into the ansible virtualenvs now so
there is no need to pull them as executor specific dependencies.

Change-Id: I3aeac278b8e1f4bb796e0f3a3f475b3c97208a85

Dockerfile

@@ -44,10 +44,7 @@ VOLUME /var/lib/zuul
 CMD ["/usr/local/bin/zuul"]
 
 FROM zuul as zuul-executor
-COPY --from=builder /output/ /output
 COPY --from=builder /usr/local/lib/zuul/ /usr/local/lib/zuul
-RUN pip install --cache-dir=/output/wheels -r /output/zuul_executor/requirements.txt \
-  && rm -rf /output
 
 CMD ["/usr/local/bin/zuul-executor"]
 

setup.cfg

@@ -54,6 +54,3 @@ migrate=
 zuul_base =
     PyMySQL
     psycopg2-binary
-zuul_executor =
-    ara
-    openstacksdk