release the packet buffer after sending a CONNECTION_CLOSE in the server

[marten-seemann]

No description provided.

[codecov]

Codecov Report

Merging #2935 (fb99516) into master (deacefd) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2935   +/-   ##
=======================================
  Coverage   86.22%   86.22%           
=======================================
  Files         132      132           
  Lines        9141     9142    +1     
=======================================
+ Hits         7881     7882    +1     
  Misses        910      910           
  Partials      350      350           

Impacted Files	Coverage Δ
server.go	83.33% <100.00%> (+0.05%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update deacefd...fb99516. Read the comment docs.