fix: http parse pb message body panic

[shifengbin]

fix #2782

[codecov-commenter]

Codecov Report

Merging #2847 (6933316) into main (96480c1) will increase coverage by 0.09%.
The diff coverage is 83.33%.

❗ Current head 6933316 differs from pull request most recent head 11fbdda. Consider uploading reports for the commit 11fbdda to get more accurate results

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@@            Coverage Diff             @@
##             main    #2847      +/-   ##
==========================================
+ Coverage   84.48%   84.57%   +0.09%     
==========================================
  Files          88       88              
  Lines        3925     3936      +11     
==========================================
+ Hits         3316     3329      +13     
+ Misses        434      433       -1     
+ Partials      175      174       -1     

Impacted Files	Coverage Δ
encoding/proto/proto.go	89.47% <83.33%> (-10.53%)	⬇️

... and 2 files with indirect coverage changes