Fix some errors in doc

[Gujiawei-Edinburgh]

1. fix link error in README;
2. remove unused email address.

[coveralls]

Pull Request Test Coverage Report for Build 16269233856

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 46 unchanged lines in 16 files lost coverage.
• Overall coverage decreased (-0.09%) to 63.142%

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Files with Coverage Reduction	New Missed Lines	%
org/apache/bifromq/basecluster/memberlist/agent/Agent.java	1	95.16%
org/apache/bifromq/basecluster/transport/TCPTransport.java	1	89.05%
org/apache/bifromq/basekv/raft/RaftNodeStateLeader.java	1	84.91%
org/apache/bifromq/basekv/store/wal/KVRangeWAL.java	1	93.33%
org/apache/bifromq/basekv/store/wal/KVRangeWALSubscription.java	1	95.31%
org/apache/bifromq/starter/utils/ClusterDomainUtil.java	1	75.0%
org/apache/bifromq/basecrdt/core/internal/InMemReplicaStateLattice.java	2	94.19%
org/apache/bifromq/basecrdt/service/CRDTCluster.java	2	81.91%
org/apache/bifromq/basekv/raft/RaftNodeStateFollower.java	2	82.45%
org/apache/bifromq/basekv/store/range/KVRange.java	2	93.75%

Totals
Change from base Build 16165050678:	-0.09%
Covered Lines:	23307
Relevant Lines:	35674

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💛 - Coveralls