Fix cleanup_value enrichment

[lthurston]

@amywieliczka @barbarahui

I'm deleting the other PR related to this enrichment, as it's not particularly useful.

[amywieliczka]

The cleanup_values enrichment updates implemented here did resolve many "errors" in the validation reports for Flickr collections, but as it turns out, many of these errors were actually desirable, so the cleanup_values enrichment updates did wind up having some mildly adverse affects on the already approved Flickr metadata. Since these adverse affects aren't any worse than what is already published in Calisphere, though, we're moving a cleanup_values analysis into post-MVP. Specifically, at this point in time, cleanup_values removes many trailing periods from the title field for Flickr collections.

This spreadsheet https://docs.google.com/spreadsheets/d/19vvscRbGSqztr7mDBoL4d3KTBZrC8LeK68dETspl0tE/edit?usp=sharing lists all validation errors that had previously existed in the Flickr validation reports and, upon merging this PR, no longer exist in the Flickr validation reports. There were no new errors reported. There was one error that transformed: the legacy date value for this record is None, and the Rikolti value prior to this update was ['Dec.'], but the Rikolti value after this update is ['Dec']:

"27324--21445057170","date","None","['Dec.']","https://calisphere.org/search/?q=27324--21445057170","https://harvest-prd.cdlib.org/solr/dc-collection/select?q=harvest_id_s%3A%2227324--21445057170%22&wt=json&indent=true","https://harvest-prd.cdlib.org/couchdb/_utils/document.html?ucldc/27324--21445057170","https://calisphere-test.cdlib.org/search/?q=27324--21445057170","https://harvest-stg.cdlib.org/solr/dc-collection/select?q=harvest_id_s%3A%2227324--21445057170%22&wt=json&indent=true","https://harvest-stg.cdlib.org/couchdb/_utils/document.html?ucldc/27324--21445057170"
"27324--21445057170","date","None","['Dec']","https://calisphere.org/search/?q=27324--21445057170","https://harvest-prd.cdlib.org/solr/dc-collection/select?q=harvest_id_s%3A%2227324--21445057170%22&wt=json&indent=true","https://harvest-prd.cdlib.org/couchdb/_utils/document.html?ucldc/27324--21445057170","https://calisphere-test.cdlib.org/search/?q=27324--21445057170","https://harvest-stg.cdlib.org/solr/dc-collection/select?q=harvest_id_s%3A%2227324--21445057170%22&wt=json&indent=true","https://harvest-stg.cdlib.org/couchdb/_utils/document.html?ucldc/27324--21445057170"

Creating a GitHub issue for the future cleanup_values analysis and linking this PR and comment.