* app/vmauth: add concurent requests limit per auth record
* app/vmauth: added clarification comment
* app/vmauth: remove unused code
* app/vmauth: move read from limiter
* app/vmauth: fix text
* app/vmauth: fix comments
* - Clarify the docs for the max_concurrent_requests option at docs/vmauth.md
- Clarify the description of the change at docs/CHANGELOG.md
- Make sure that the -maxConcurrentRequests takes precedence over per-user max_concurrent_requests
- Update tests for verifying that the max_concurrent_requests option is parsed properly
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3346
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Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>