For xpro, conditionally ingest topics for each resource depending on formatting

[mbertrand]

Blocked until the production xpro api has been fully updated with mit-learn topics.

What are the relevant tickets?

Closes https://github.com/mitodl/hq/issues/5551

Description (What does it do?)

Adjusts the xpro ETL pipeline to no longer transform topics. Any topic names matching mit-learn topics will be assigned, others will be ignored.

How can this be tested?

• Set the following backend env variables:

  XPRO_CATALOG_API_URL=https://xpro.mit.edu/api/programs/
  XPRO_COURSES_API_URL=https://xpro.mit.edu/api/courses/
  ``
  

• Run ./manage.py backpopulate_xpro_data, it should complete without errors.
• Go to https://learn.mit.edu/search?offered_by=xpro, compare with https://xpro.mit.edu/api/courses/: only topics that match mit-learn topics should have been assigned (so, no topics with a ":" for example).