Pass the current API file to the metalava --use-same-format-as option

That will allow the format of a file to be changed by simply modifying
the signature format in the current API file (e.g. from `2.0` to `3.0`)
and then running `m update-api` and it will just update the current API
file (and the corresponding removed API file).

Bug: 295577788
Test: m checkapi && m update-api
      # Also did as described above and modified the
      # `libcore/api/current.txt` file from `2.0` to `3.0` and ran
      # `m update-api` and checked that only that file and the
      # corresponding `removed.text` file was changed.
Change-Id: I20c9bc151677502cf09b0c06fb442fd385caccdd