fix:修复发布实例事件可能导致的程序panic问题 & 实例变更事件不应打印 InstanceUpdateEvent

[chuntaojun]

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[polaris-test-bot]

2023-03-20 09:53:47: =========TEST START==========
2023-03-20 09:54:14: Pre-Merge check success! Now we will perform a full automated test which is expected to take 2 hours, thank you for your patience.
2023-03-20 10:09:14: [STANDALONE VERSION]PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/sta/qta-report.html
2023-03-20 10:09:18: [CLUSTER VERSION] PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/clu/qta-report.html
2023-03-20 10:09:21: [KUBENETES VERSION]PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/k8s/qta-report.html
2023-03-20 10:23:51: =========TEST START==========
2023-03-20 10:24:18: Pre-Merge check success! Now we will perform a full automated test which is expected to take 2 hours, thank you for your patience.
2023-03-20 10:37:26: [STANDALONE VERSION]PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/sta/qta-report.html
2023-03-20 10:37:30: [CLUSTER VERSION] PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/clu/qta-report.html
2023-03-20 10:37:33: [KUBENETES VERSION]PR autotest PASSED! We executed 20 test cases and 20 were passed. You can see test report in https://polaris-opentest-1306863770.cos.ap-guangzhou.myqcloud.com/pr1281865424/k8s/qta-report.html
2023-03-20 10:46:33: =========TEST START==========

[codecov]

Codecov Report

Merging #1025 (42d9e9b) into main (a1551c9) will increase coverage by 0.03%.
The diff coverage is 43.75%.

❗ Current head 42d9e9b differs from pull request most recent head 1873ed1. Consider uploading reports for the commit 1873ed1 to get more accurate results

@@            Coverage Diff             @@
##             main    #1025      +/-   ##
==========================================
+ Coverage   57.90%   57.94%   +0.03%     
==========================================
  Files         191      191              
  Lines       34408    34408              
==========================================
+ Hits        19924    19936      +12     
+ Misses      11898    11881      -17     
- Partials     2586     2591       +5     

Impacted Files	Coverage Δ
service/client_v1.go	53.94% <0.00%> (-0.41%)	⬇️
service/healthcheck/server.go	31.60% <100.00%> (+1.19%)	⬆️
service/instance.go	62.23% <100.00%> (+0.38%)	⬆️

... and 8 files with indirect coverage changes

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