Merge branch 'bc/filter-process'

Merge branch 'bc/filter-process'

Provide more information (e.g. the object of the tree-ish in which
the blob being converted appears, in addition to its path, which
has already been given) to smudge/clean conversion filters.

* bc/filter-process:
  t0021: test filter metadata for additional cases
  builtin/reset: compute checkout metadata for reset
  builtin/rebase: compute checkout metadata for rebases
  builtin/clone: compute checkout metadata for clones
  builtin/checkout: compute checkout metadata for checkouts
  convert: provide additional metadata to filters
  convert: permit passing additional metadata to filter processes
  builtin/checkout: pass branch info down to checkout_worktree