fix: Reduce the chance of `CurlEventPublisher` exhausting file descriptors on high throughput PHP-FPM servers#216

keelerm84 merged 3 commits intolaunchdarkly:mainlaunchdarkly/php-server-sdk:mainfrom

Watercycle:event-publisher-resiliencyWatercycle/php-server-sdk:event-publisher-resiliencyCopy head branch name to clipboard