Update for 8.5.fb branch cut

HISTORY.md

 # Rocksdb Change Log
 > NOTE: Entries for next release do not go here. Follow instructions in `unreleased_history/README.txt`
 
+## 8.5.0 (07/21/2023)
+### Public API Changes
+* Removed recently added APIs `GeneralCache` and `MakeSharedGeneralCache()` as our plan changed to stop exposing a general-purpose cache interface. The old forms of these APIs, `Cache` and `NewLRUCache()`, are still available, although general-purpose caching support will be dropped eventually.
+
+### Behavior Changes
+* Option `periodic_compaction_seconds` no longer supports FIFO compaction: setting it has no effect on FIFO compactions. FIFO compaction users should only set option `ttl` instead.
+* Move prefetching responsibility to page cache for compaction read for non directIO use case
+
+### Performance Improvements
+* In case of direct_io, if buffer passed by callee is already aligned, RandomAccessFileRead::Read will avoid realloacting a new buffer, reducing memcpy and use already passed aligned buffer.
+* Small efficiency improvement to HyperClockCache by reducing chance of compiler-generated heap allocations
+
 ## 8.4.0 (06/26/2023)
 ### New Features
 * Add FSReadRequest::fs_scratch which is a data buffer allocated and provided by underlying FileSystem to RocksDB during reads, when FS wants to provide its own buffer with data instead of using RocksDB provided FSReadRequest::scratch. This can help in cpu optimization by avoiding copy from file system's buffer to RocksDB buffer. More details on how to use/enable it in file_system.h. Right now its supported only for MultiReads(async + sync) with non direct io.

unreleased_history/behavior_changes/fifo_ttl_periodic_compaction.md

-Option `periodic_compaction_seconds` no longer supports FIFO compaction: setting it has no effect on FIFO compactions. FIFO compaction users should only set option `ttl` instead.
\ No newline at end of file

unreleased_history/behavior_changes/fs_prefetch_compaction_read.md

-Move prefetching responsibility to page cache for compaction read for non directIO use case

unreleased_history/performance_improvements/avoid_memcpy_directio.md

-In case of direct_io, if buffer passed by callee is already aligned, RandomAccessFileRead::Read will avoid realloacting a new buffer, reducing memcpy and use already passed aligned buffer.

unreleased_history/performance_improvements/hcc_perf

-Small efficiency improvement to HyperClockCache by reducing chance of compiler-generated heap allocations

unreleased_history/public_api_changes/rename_migration_caches.md

-Removed recently added APIs `GeneralCache` and `MakeSharedGeneralCache()` as our plan changed to stop exposing a general-purpose cache interface. The old forms of these APIs, `Cache` and `NewLRUCache()`, are still available, although general-purpose caching support will be dropped eventually.

unreleased_history/release.sh

@@ -31,7 +31,7 @@ awk '/#define ROCKSDB_MAJOR/ { major = $3 }
      /#define ROCKSDB_MINOR/ { minor = $3 }
      /#define ROCKSDB_PATCH/ { patch = $3 }
      END { printf "## " major "." minor "." patch }' < include/rocksdb/version.h >> HISTORY.new
-echo " (`date +%x`)" >> HISTORY.new
+echo " (`git log -n1 --date=format:"%m/%d/%Y" --format="%ad"`)" >> HISTORY.new
 
 function process_file () {
   # use awk to correct extra or missing newlines, missing '* ' on first line