Author Merges sometimes (always?) not reflected in author search

After authors are merged, the redirect records still sometimes (always?) appear in author search. A forced re-index of the author id fixes the problem.

### Relevant url?
eg https://openlibrary.org/search/authors?q=alcott&mode=everything -- Note https://openlibrary.org/authors/OL9635536A is still visible despite being a redirect.

### Steps to Reproduce

1. Merge some authors
2. Perform a search that should show the authors

* Actual: The redirect author is still there
* Expected: The redirect author should have disappeared

### Details

- **Logged in (Y/N)?**
- **Browser type/version?**
- **Operating system?**
- **Environment (prod/dev/local)?** prod

### Proposal & Constraints

### Related files

### Stakeholders
@seabelis