Improve monitor creating, handle errors

[kylixs]

What is the purpose of the change

Fix the problem that if an exception is thrown when creating a monitor, it is not handled correctly.

Brief changelog

Verifying this change

Checklist

• Make sure there is a GitHub_issue field for the change (usually before you start working on it). Trivial changes like typos do not require a GitHub issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
• Each commit in the pull request should have a meaningful subject line and body.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Check if is necessary to patch to Dubbo 3 if you are work on Dubbo 2.7
• Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Add some description to dubbo-website project if you are requesting to add a feature.
• GitHub Actions works fine on your own branch.
• If this contribution is large, please follow the Software Donation Guide.

[codecov-commenter]

Codecov Report

Merging #7867 (c04fc43) into master (2dace54) will decrease coverage by 0.30%.
The diff coverage is 70.00%.

@@             Coverage Diff              @@
##             master    #7867      +/-   ##
============================================
- Coverage     59.60%   59.29%   -0.31%     
- Complexity      556      557       +1     
============================================
  Files          1088     1088              
  Lines         43854    43847       -7     
  Branches       6400     6400              
============================================
- Hits          26140    26000     -140     
- Misses        14814    14951     +137     
+ Partials       2900     2896       -4     

Impacted Files	Coverage Δ
.../dubbo/monitor/support/AbstractMonitorFactory.java	80.00% <70.00%> (+1.62%)	⬆️
...a/org/apache/dubbo/rpc/filter/AccessLogFilter.java	28.35% <0.00%> (-50.75%)	⬇️
...va/org/apache/dubbo/rpc/support/AccessLogData.java	53.16% <0.00%> (-37.98%)	⬇️
...ng/transport/dispatcher/all/AllChannelHandler.java	68.96% <0.00%> (-27.59%)	⬇️
...dubbo/common/status/support/LoadStatusChecker.java	46.15% <0.00%> (-15.39%)	⬇️
...rg/apache/dubbo/remoting/utils/PayloadDropper.java	76.92% <0.00%> (-15.39%)	⬇️
...ng/transport/dispatcher/WrappedChannelHandler.java	43.47% <0.00%> (-15.22%)	⬇️
.../apache/dubbo/rpc/protocol/AsyncToSyncInvoker.java	62.06% <0.00%> (-10.35%)	⬇️
...dubbo/remoting/exchange/support/DefaultFuture.java	78.63% <0.00%> (-8.55%)	⬇️
.../dubbo/remoting/transport/netty4/NettyChannel.java	56.43% <0.00%> (-7.93%)	⬇️
... and 11 more

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[icankeep]

FUTURES.remove(key);

the code seem to be unnecessary

[kylixs]

Clean up future objects