Hotfix 6.0.x sup 16004

[plyhun]

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[plyhun]

Here we cannot reuse an existing SymlinkAllowedResourceAliasChecker for two reasons.

1. It is enabled by default, thus - useless.
2. It is useless, because of its ultimate dependency on a base webroot, which is set to /webroot, which is based on an application classpath root, and not the root we set in the distinct handler.

[plyhun]

NB: Fresher Jetty version extends the possibility of AliasCheckers, though it requires a refactoring / overall stability check.
jetty/jetty.project#8259

[npomaroli]

Tested with the example setup of the ticket and it did not work (static file from symlinked package is not availalbe).

[plyhun]

Tested with the example setup of the ticket and it did not work (static file from symlinked package is not availalbe).

I was able to replicate the issue on a local setup. Will re-check with the provided docker environment as well.