[ISSUE #7868] Use entrySet to close channel

[ChineseTony]

Which Issue(s) This PR Fixes

Fixes #7868

Brief Description

How Did You Test This Change?

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 40.00000% with 3 lines in your changes are missing coverage. Please review.

Project coverage is 42.93%. Comparing base (471dbc0) to head (c875de2).
Report is 1 commits behind head on develop.

Files	Patch %	Lines
...e/rocketmq/remoting/netty/NettyRemotingClient.java	40.00%	3 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop    #7869      +/-   ##
=============================================
- Coverage      42.95%   42.93%   -0.03%     
- Complexity      9913     9916       +3     
=============================================
  Files           1190     1190              
  Lines          86016    86017       +1     
  Branches       11080    11080              
=============================================
- Hits           36948    36929      -19     
- Misses         44495    44522      +27     
+ Partials        4573     4566       -7     

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[glcrazier]

Do you have any statistical support for this enhancement?

[ChineseTony]

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Threads;
import org.openjdk.jmh.annotations.Warmup;

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;

@BenchmarkMode(Mode.Throughput)
@Warmup(iterations = 3, time = 1)
@Measurement(iterations = 5, time = 3)
@Fork(1)
@State(value = Scope.Benchmark)
@OutputTimeUnit(TimeUnit.SECONDS)

public class MapUtil {
    private Map<String, String> map = new HashMap<>();

    @Setup
    public void setup() {
        for (int i = 0; i < 8000; i++) {
            map.put(i + "", i + "");
        }
    }

    @Benchmark
    @Threads(8)
    public void keySetMap() {
        keySet();
    }

    @Benchmark
    @Threads(8)
    public void entrySetMap() {
        entrySet();
    }

    private void entrySet() {
        for (Map.Entry<String, String> entry : map.entrySet()) {
            entry.getValue();
        }
    }

    private void keySet() {
        for (String key : map.keySet()) {
            map.get(key);
        }
    }
}

Benchmark Mode Cnt Score Error Units
MapUtil.entrySetMap thrpt 5 172067.111 ± 452324.484 ops/s
MapUtil.keySetMap thrpt 5 109211.325 ± 41925.022 ops/s