The git certificate needs to be labeled as mounted to workspace.

[metlos]

What does this PR do?

This makes sure that the git certificate is also mounted to the workspace so that the generated gitconfig points to a file that exists.

What issues does this PR fix or reference?

eclipse-che/che#21327
https://issues.redhat.com/browse/CRW-2882

How to test this PR?

1. Deploy Che and use quay.io/lkrejci/che-operator:issue-21327 as the operator image
2. Update Che installation with some git certificate

   $ kubectl create configmap che-git-self-signed-cert --from-file=<SOME_CA.CRT_FILE> --from-literal=githost=https://over.the.rainbow -n eclipse-che
   $ kubectl label configmap che-git-self-signed-cert app.kubernetes.io/part-of=che.eclipse.org -n eclipse-che
   $ kubectl patch checluster devspaces --type=json -p '[{"op": "replace", "path": "/spec/server/gitSelfSignedCert", "value": true}]' -n eclipse-che
   
   

3. Start a workspace
4. Open a terminal in the workspace
5. Check that /etc/config/che-git-self-signed-cert/certificate and /etc/config/che-git-self-signed-cert/host files exist and have the contents corresponding to the first kubectl command in the second repro step.

PR Checklist

As the author of this Pull Request I made sure that:

• The Eclipse Contributor Agreement is valid
• Code produced is complete
• Code builds without errors
• Tests are covering the bugfix
• Custom resource definition file is up to date
• OLM bundles are up to date
• The repository devfile is up to date and works
• Sections What issues does this PR fix or reference and How to test this PR completed
• Relevant user documentation updated
• Relevant contributing documentation updated
• CI/CD changes implemented, documented and communicated

Reviewers

Reviewers, please comment how you tested the PR when approving it.

[codecov]

Codecov Report

Merging #1375 (b8f6d01) into main (a269da2) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1375   +/-   ##
=======================================
  Coverage   61.89%   61.89%           
=======================================
  Files          76       76           
  Lines        6248     6249    +1     
=======================================
+ Hits         3867     3868    +1     
  Misses       1998     1998           
  Partials      383      383           

Impacted Files	Coverage Δ
controllers/usernamespace/controller.go	64.43% <100.00%> (+0.12%)	⬆️

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[nickboldt]

tests pass and this seems like a simple enough fix, so I'm happy to merge this... but will wait for more expert eyes to review.

Note that we need this backported to 7.46.x if we're going to include this in 3.0... so you can prepare that PR too, while you wait.

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: metlos, nickboldt, tolusha

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