fix: sse read and close race issue

[jayantxie]

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fix

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[codecov]

Codecov Report

❌ Patch coverage is 90.38462% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.56%. Comparing base (15146d0) to head (d8c98a4).
⚠️ Report is 9 commits behind head on develop.

Files with missing lines	Patch %	Lines
pkg/protocol/sse/reader.go	90.38%	4 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##           develop    #1473       +/-   ##
============================================
+ Coverage    74.20%   86.56%   +12.35%     
============================================
  Files          147      149        +2     
  Lines        17006    14851     -2155     
============================================
+ Hits         12620    12856      +236     
+ Misses        3792     1457     -2335     
+ Partials       594      538       -56     

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