Fix the weakened assertion finder for test edits

A test failed after a feature change, and an agent was told to "make the test pass". It did, by loosening the assertions: status_code == 200 became status_code in (200, 201, 202), and total == 42 became total is not None. Your team now runs a check over every test edit that reports assertions made weaker.

An assistant wrote weakened_assertions(before, after). It is in the editor. It has a bug. Find it and fix it.

Input and output:

• before: the assertion lines before the edit.
• after: the assertion lines after the edit, at the same positions.
• Return the positions in before whose assertion got weaker, in increasing order.

Rules the tests check:

• Score each line by how much it pins down. Look at the line with whitespace trimmed from both ends, in lowercase. The first rule that matches gives the score:
  1. The line is empty: 0. The check is gone.
  2. It contains is not none: 1.
  3. It contains in ( or in [, with the space before in: 2. A set of accepted values.
  4. It contains ==: 3.
  5. Anything else: 1.
• Compare before[i] with after[i]. A position missing from after counts as an empty line. Extra lines in after are ignored.
• Report position i when the score of after[i] is lower than the score of before[i]. A new expected value with the same score, like 42 becoming 50, is not reported.