CI: Drop OPTIONAL_DEPENDS

Author: effigies

tools/ci/install_dependencies.sh

@@ -10,7 +10,6 @@ set -eu
 # Required variables
 echo EXTRA_PIP_FLAGS = $EXTRA_PIP_FLAGS
 echo DEPENDS = $DEPENDS
-echo OPTIONAL_DEPENDS = $OPTIONAL_DEPENDS
 
 set -x
 
@@ -20,11 +19,6 @@ fi
 
 if [ -n "$DEPENDS" ]; then
     pip install ${EXTRA_PIP_FLAGS} --prefer-binary ${!DEPENDS}
-    if [ -n "$OPTIONAL_DEPENDS" ]; then
-        for DEP in ${!OPTIONAL_DEPENDS}; do
-            pip install ${EXTRA_PIP_FLAGS} --prefer-binary $DEP || true
-	done
-    fi
 fi
 
 set +eux