List devfile component without connecting cluster if experimental flag is enabled

[GeekArthur]

Signed-off-by: jingfu wang jingfu.j.wang@ibm.com

What type of PR is this?
/kind bug

What does does this PR do / why we need it:
If the experimental flag is enabled, user should be able to list devfile components even if user doesn't connect to OpenShift cluster. Instead of failing the odo catalog list components, we output the following warning to user:

odo catalog list components                                                                                  ✔  17:00:33 
 ⚠  Please log in to an OpenShift cluster to list OpenShift/s2i components

Odo Supported Devfile Components:
NAME                 DESCRIPTION
java-spring-boot     Spring Boot® using IBM Java
openLiberty          Open Liberty microservice in Java

Which issue(s) this PR fixes:
Fixes #2740
Fixes #2706

How to test changes / Special notes to the reviewer:

[GeekArthur]

/assign

[GeekArthur]

@kadel Please review this PR, thanks!

[johnmcollier]

One quick comment and a question Jingfu

[GeekArthur]

@cdrage @johnmcollier Comments addressed, please review again, thanks!

[GeekArthur]

/retest

[codecov]

Codecov Report

Merging #2749 into master will decrease coverage by 0.2%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #2749      +/-   ##
=========================================
- Coverage   43.71%   43.5%   -0.21%     
=========================================
  Files          87      91       +4     
  Lines        8066    8222     +156     
=========================================
+ Hits         3526    3577      +51     
- Misses       4193    4297     +104     
- Partials      347     348       +1

Impacted Files	Coverage Δ
pkg/kclient/deployments.go	34.66% <0%> (-54.99%)	⬇️
pkg/application/application.go	41.26% <0%> (-6.01%)	⬇️
...g/devfile/adapters/kubernetes/component/adapter.go	33.67% <0%> (-0.53%)	⬇️
pkg/lclient/images.go	60% <0%> (ø)
pkg/lclient/fakeclient.go	42.62% <0%> (ø)
pkg/lclient/client.go	0% <0%> (ø)
pkg/lclient/containers.go	88.88% <0%> (ø)
pkg/occlient/occlient.go	52.82% <0%> (+0.02%)	⬆️
pkg/component/watch.go	74% <0%> (+1.33%)	⬆️

---

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[GeekArthur]

/retest

[GeekArthur]

/retest

[kadel]

comments addressed, and this is a small change

/approve
/lgtm

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kadel

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• OWNERS [kadel]

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