*: update etcd

[nolouch]

What problem does this PR solve?

• customized etcd logger
• fix prevote bug
• fast drop propose and read
• fix the issue about renew a lease with long TTL.
• Improve backend ( boltDB

What is changed and how it works?

update etcd.

Check List

Tests

• Unit test
• Integration test

[nolouch]

/run-all-tests

[zhouqiang-cl]

/run-all-tests

[zhouqiang-cl]

/rebuild

[zhouqiang-cl]

/rebuild

[zhouqiang-cl]

/rebuild

[rleungx]

@nolouch This PR could be merged now?

[nolouch]

@rleungx Yes, this PR already running 5 days in schordinger and no problem now, I think we can merge it.

[codecov-io]

Codecov Report

Merging #1452 into master will decrease coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1452      +/-   ##
==========================================
- Coverage   67.25%   67.22%   -0.03%     
==========================================
  Files         158      158              
  Lines       15383    15385       +2     
==========================================
- Hits        10346    10343       -3     
- Misses       4099     4106       +7     
+ Partials      938      936       -2

Impacted Files	Coverage Δ
pkg/logutil/log.go	85.27% <ø> (ø)	⬆️
tests/cluster.go	83.33% <ø> (ø)	⬆️
server/join.go	55.4% <ø> (ø)	⬆️
server/tso.go	72.72% <ø> (ø)	⬆️
server/util.go	70.27% <ø> (ø)	⬆️
tools/pd-ctl/pdctl/command/global.go	41.66% <ø> (ø)	⬆️
server/etcd_kv.go	74.54% <ø> (+3.63%)	⬆️
server/api/utiletcdhttpapi.go	77.77% <ø> (ø)	⬆️
server/id.go	72.97% <ø> (ø)	⬆️
server/server.go	77.72% <ø> (-0.5%)	⬇️
... and 13 more

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