This is an automated cherry-pick of #10055

What problem does this PR solve?

Issue Number: close #10052

Problem Summary:

# tidb.toml
[performance]
txn-entry-size-limit = 125829120
# tiup edit
#    performance.txn-entry-size-limit: 125829120

# tikv.toml
[raftstore]
raft-entry-max-size = '120MiB'
# tiup edit
#     raftstore.raft-entry-max-size: '120MiB'

set global max_allowed_packet = 1073741824;
CREATE TABLE `t` (
  `id` bigint(21) unsigned NOT NULL,
  `text` longtext DEFAULT NULL
);

TiDB could allow a raft-log with 120MiB at max, while TiFlash Region::deserialize use readBinary2<std::string> only allow 16MiB at max. So if there are some raftlog larger than 16MiB and flushed to RegionData, then TiFlash could fail to restart when restoring Region data from disk.
If the raftlog is committed, the rows are decoded into Block and write down to IStorage. Reading/writing rows larger than 16MiB in the IStorage layer does not cause any error.

What is changed and how it works?

KVStore: Fix restoring large tikv value
Add function `readTiKVStringBinary` for `TiKVValue::deserialize` and `TiKVKey::deserialize` to allow restoring tikv key/values at most 120MiB

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Fix an issue that TiFlash may fail to restart when user write rows larger than 16MiB