feat: Deprecate 'self-signed-cert' flag and implement autodetection for it

[mmorhun]

Signed-off-by: Mykola Morhun mmorhun@redhat.com

What does this PR do?

Deprecates self-signed-cert option of server:start command.
In case of Operator installer this is handled on operator side, see eclipse-che/che-operator#285
In case of Helm installer, chectl checks whether self-signed-certificate secret exists and based on that makes conclusion if self-signed certificate is used and put the value into Helm chart.

What issues does this PR fix or reference?

Issue: eclipse-che/che#16764
Depends on: eclipse-che/che#17044 and eclipse-che/che-operator#285

Tests

Tested on:

• Minikube (Operator and Helm installers)
• CRC (Operator installer)
• Openshift (Operator installer with oAuth)
• Openshift (OLM installer)

[AndrienkoAleksandr]

You have unused imports.

[tolusha]

Don't forget yarn pack

[mmorhun]

From e2e tests log:

++ cico node get -f value -c ip_address -c comment
The requested operation failed as no inventory is available.
+ cico_output=
+ '[' 1 -eq 0 ']'
+ '[' 16 -gt 15 ']'
+ echo 'giving up on '\''cico node get'\'''
giving up on 'cico node get'
+ exit 1
Build step 'Execute shell' marked build as failure

Seems the problem is with CI node availability.
Merging this PR as it is should be merged together with eclipse-che/che#17044, but current PR check requires eclipse-che/che#17044 to be merged. To avoid broken things merging now.