Switch from local bootstrap and bootstrap-icons to their WebJars resources

[peutch]

Hi,

Following my remark about the use of WebJars in issue #354, here is an attempt to migrate struts2-bootstrap as an illustration.
I think it could simplify upgrading the dependency to Bootstrap and Bootstrap Icons components.
Note that it also includes a small fix 4ca2fbf.

Regards,
Patrice

[lukaszlenart]

but shouldn't we add support for WebJars into Struts itself?

[peutch]

I think at least something could be done in the same way for struts2-jquery if there is interest in it.

[lukaszlenart]

I meant to add support for /webjars/* endpoint, currently Struts is serving static content using only /static/*, an example
https://www.baeldung.com/maven-webjars#Simple

[peutch]

Could struts.ui.staticContentPath be a list?

[gregh3269]

The down side is it does make it more difficult to debug (ie adding console.log) as the assets are in a jar.

Also don't want the pom versions managed by renovate bot.

[lukaszlenart]

Could struts.ui.staticContentPath be a list?

It can be, but I would rather add a dedicated logic to serve WebJars, something like struts.serve.webJars=true and then struts.ui.webJarsPath=/webjars

[lukaszlenart]

I'm going to add support for webjars in the framework itself and then implement it here
apache/struts#1765