Merge branch 'ps/for-each-ref-in-fixes'

A handful of places used refs_for_each_ref_in() API incorrectly,
which has been corrected.

* ps/for-each-ref-in-fixes:
  bisect: simplify string_list memory handling
  bisect: fix misuse of `refs_for_each_ref_in()`
  pack-bitmap: fix bug with exact ref match in "pack.preferBitmapTips"
  pack-bitmap: deduplicate logic to iterate over preferred bitmap tips

diff --cc bisect.c
Simple merge

diff --cc builtin/pack-objects.c
Simple merge