EAR-2352 - Piping into the introduction page

[sudeepkunhis]

https://jira.ons.gov.uk/browse/EAR-2352

How to review

Follow all the steps given in the PR - ONSdigital/eq-author-app#3110

After piping the list supplementary data, check that the introduction page title in the convert schema is as given below.

"title": {
"text": "Information you need - {localunits_name}",
"placeholders": [
{
"placeholder": "localunits_name",
"transforms": [
{
"transform": "concatenate_list",
"arguments": {
"list_to_concatenate": {
"identifier": "local-units",
"source": "supplementary_data",
"selectors": [
"name"
]
},
"delimiter": ", "
}
}
]
}
]
},