Don't call auth service for user's OpenShift username

[surajssd]

Now that we have the user's OpenShift username stored in the tenant's
database, now we can stop calling auth and directly fetch it from the
database.

Fixes openshiftio/openshift.io#2635

[alien-ike]

Ike Plugins (test-keeper)

Thank you @surajssd for this contribution!

It appears that no tests have been added or updated in this PR.

Automated tests give us confidence in shipping reliable software. Please add some as part of this change.

If you are an admin or the reviewer of this PR and you are sure that no test is needed then you can use the command /ok-without-tests as a comment to make the status green.

For more information please head over to official documentation. You can find there how to configure the plugin.

[fabric8cd]

@surajssd snapshot fabric8-tenant image is available for testing. docker pull docker.io/fabric8/fabric8-tenant:SNAPSHOT-PR-610-1

[codecov-io]

Codecov Report

Merging #610 into master will increase coverage by 0.15%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master    #610      +/-   ##
=========================================
+ Coverage   35.25%   35.4%   +0.15%     
=========================================
  Files          31      31              
  Lines        2096    2087       -9     
=========================================
  Hits          739     739              
+ Misses       1268    1259       -9     
  Partials       89      89

Impacted Files	Coverage Δ
controller/tenant.go	12.5% <0%> (+0.37%)	⬆️

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[alexeykazakov]

Please add tests.

[fabric8cd]

@surajssd snapshot fabric8-tenant image is available for testing. docker pull docker.io/fabric8/fabric8-tenant:SNAPSHOT-PR-610-2