Add example command for collecting artifacts

[Yann-P]

As a beginner with act, it took me some time to find this comment and figure out how to access the artifacts #329 (comment).

I had read --help but it was not clear that an artifact server was included and thought I had to provide an URI to an external service.

So I suggest adding this small example -- alternatively add a note to the wiki

[mergify]

@Yann-P this pull request has failed checks 🛠

[Yann-P]

@KnisterPeter can you approve the workflow again please?

[ChristopherHX]

Please note documentation is moving

https://nektosact.com/beginner/index.html

• Documentation is moving to https://github.com/nektos/act-docs

[codecov]

Codecov Report

Merging #1671 (3d52e49) into master (4989f44) will increase coverage by 1.59%.
The diff coverage is 74.20%.

@@            Coverage Diff             @@
##           master    #1671      +/-   ##
==========================================
+ Coverage   61.22%   62.81%   +1.59%     
==========================================
  Files          46       48       +2     
  Lines        7141     7479     +338     
==========================================
+ Hits         4372     4698     +326     
+ Misses       2462     2461       -1     
- Partials      307      320      +13     

Impacted Files	Coverage Δ
pkg/container/docker_cli.go	82.23% <ø> (ø)
pkg/container/docker_logger.go	52.08% <ø> (ø)
pkg/container/docker_pull.go	33.33% <ø> (ø)
pkg/container/docker_run.go	14.08% <0.00%> (+0.49%)	⬆️
pkg/container/docker_volume.go	0.00% <ø> (ø)
pkg/container/file_collector.go	37.30% <0.00%> (ø)
pkg/container/host_environment.go	0.00% <0.00%> (ø)
pkg/exprparser/functions.go	66.32% <0.00%> (-1.04%)	⬇️
pkg/model/workflow.go	42.11% <ø> (ø)
pkg/model/planner.go	44.71% <21.27%> (-4.12%)	⬇️
... and 20 more

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more