fix command line syntax error from #10463

[ewdurbin]

containers were failing to build with:

 > [build 8/8] RUN set -x     && pip --no-deps --no-cache-dir --disable-pip-version-check             install --no-binary hiredis                     -r /tmp/requirements/deploy.txt                     -r /tmp/requirements/main.txt                     $(if [ "yes" = "yes" ]; then echo '-r /tmp/requirements/tests.txt -r /tmp/requirements/lint.txt'; fi)     && find /opt/warehouse -name '*.pyc' -delete:
#28 0.969 + [ yes = yes ]
#28 0.969 + echo -r /tmp/requirements/tests.txt -r /tmp/requirements/lint.txt
#28 0.970 + pip --no-deps --no-cache-dir --disable-pip-version-check install --no-binary hiredis -r /tmp/requirements/deploy.txt -r /tmp/requirements/main.txt -r /tmp/requirements/tests.txt -r /tmp/requirements/lint.txt
#28 1.518 
#28 1.518 Usage:   
#28 1.518   pip <command> [options]
#28 1.518 
#28 1.518 no such option: --no-deps
------
executor failed running [/bin/sh -c set -x     && pip --no-deps --no-cache-dir --disable-pip-version-check             install --no-binary hiredis                     -r /tmp/requirements/deploy.txt                     -r /tmp/requirements/main.txt                     $(if [ "$DEVEL" = "yes" ]; then echo '-r /tmp/requirements/tests.txt -r /tmp/requirements/lint.txt'; fi)     && find /opt/warehouse -name '*.pyc' -delete]: exit code: 2
ERROR: Service 'web' failed to build : Build failed