In container demo tutorial, can't update Solr fields after adding additional metadata block

[pdurbin]

As someone trying to follow https://guides.dataverse.org/en/6.7.1/container/running/demo.html#additional-metadata-blocks I'm getting this error:

% curl http://localhost:8080/api/admin/index/solr/schema | docker run -i --rm -v ./docker-dev-volumes/solr/data:/var/solr gdcc/configbaker:unstable update-fields.sh /var/solr/data/collection1/conf/schema.xml
ERROR: Please ensure ed, bc, sed + awk are installed
curl: (23) Failure writing output to destination, passed 16384 returned 0

I can only assume this is because we switched from Alpine to Ubuntu in Dataverse 6.7 as part of #11477: 7e8969b

I'll make a PR.