fix(epoll): use E prefixed events for linux epoll event notifications

[StarpTech]

Motivation and Context

This requires further testing. The assumption is that on different OS different flags are used and that unix.POLLIN | unix.POLLHUP were not correct to use EPOLL on these systems.

Checklist

• I have discussed my proposed changes in an issue and have received approval to proceed.
• I have followed the coding standards of the project.
• Tests or benchmarks have been added or updated.
• Documentation has been updated on https://github.com/wundergraph/cosmo-docs.
• I have read the Contributors Guide.