Merge branch 'ps/reftable-reflog-iteration-perf'

The code to iterate over reflogs in the reftable has been optimized to reduce memory allocation and deallocation. Reviewed-by: Josh Steadmon <steadmon@google.com> cf. <Ze9eX-aaWoVaqsPP@google.com> * ps/reftable-reflog-iteration-perf: refs/reftable: track last log record name via strbuf reftable/record: use scratch buffer when decoding records reftable/record: reuse message when decoding log records reftable/record: reuse refnames when decoding log records reftable/record: avoid copying author info reftable/record: convert old and new object IDs to arrays refs/reftable: reload correct stack when creating reflog iter