Add periodic topic collection sync task

[shanbady]

What are the relevant tickets?

Related to item missed in previous PR and https://github.com/mitodl/hq/issues/9056

Description (What does it do?)

This PR adds the scheduled task to update the topics collection which was missed in a previous pr.

How can this be tested?

1. checkout this branch
2. run the task manually and see that it succeeds:

from vector_search.tasks import sync_topics
sync_topics()

[github-actions]

OpenAPI Changes

Show/hide 3 changes: 0 error, 0 warning, 3 info

3 changes: 0 error, 0 warning, 3 info
info	[request-parameter-property-type-generalized] at head/openapi/specs/v1.yaml	
	in API GET /api/v1/contentfiles/
		for the 'query' request parameter 'resource_id', the type/format of property '/items/' was generalized from 'integer'/'' to 'number'/''

info	[request-parameter-property-type-generalized] at head/openapi/specs/v1.yaml	
	in API GET /api/v1/courses/{learning_resource_id}/contentfiles/
		for the 'query' request parameter 'resource_id', the type/format of property '/items/' was generalized from 'integer'/'' to 'number'/''

info	[request-parameter-property-type-generalized] at head/openapi/specs/v1.yaml	
	in API GET /api/v1/learning_resources/{learning_resource_id}/contentfiles/
		for the 'query' request parameter 'resource_id', the type/format of property '/items/' was generalized from 'integer'/'' to 'number'/''

Unexpected changes? Ensure your branch is up-to-date with main (consider rebasing).

[mbertrand]

👍