evaluate replace directive in go.mod

[leehinman]

Currently the beats go.mod file has 20 replace directives, and many of these replace all versions of the module with the specified one. Many of these were added to get around a specific bug, but upstream has often fixed the issue. We should be removing the replace directives when possible, and documenting why they are required. We should also come up with some best practices for adding replace directives, examples might be forks should be maintained by elastic, include version number on left side when possible to reduce scope, etc.

One example:

	github.com/fsnotify/fsnotify => github.com/adriansr/fsnotify v1.4.8-0.20211018144411-a81f2b630e7c

This replaces all versions of fsnotify with a very specific fork that is not maintained by elastic. The last time this was updated was to get around a limitation in fsnotify that has now been fixed.

[elasticmachine]

Pinging @elastic/elastic-agent (Team:Elastic-Agent)