fix: retry requests when idle pooled socket closes

[mcollina]

Summary

• retry idempotent HTTP/1.1 requests when an idle pooled socket closes before reuse
• retry idempotent HTTP/2 requests on abrupt idle socket close while preserving GOAWAY handling
• add separate regression coverage for the HTTP/1.1 and HTTP/2 races

Fixes: #3492

Testing

• ./node_modules/.bin/borp --timeout 180000 --expose-gc -p "test/issue-3492.js"
• ./node_modules/.bin/borp --timeout 300000 --expose-gc -p "test/http2-goaway.js"
• ./node_modules/.bin/borp --timeout 180000 --expose-gc -p "test/http2-connection.js"
• npm run lint -- lib/dispatcher/client-h1.js lib/dispatcher/client-h2.js test/issue-3492.js

[mcollina]

I’m not convinced we should
do this.

[ronag]

Wouldn't this be cleaner in the retry interceptor? Seems over complex here.