[AKS] rename admin k8s context so it won't overwite user context

[mboersma]

Fixes an issue where az aks get-credentials didn't distinguish between the admin and user versions when merging into ~/.kube/config.

Before:

$ rm -f ~/.kube/config
$ az aks get-credentials -g aztest -n aztest
Merged "aztest" as current context in /Users/matt/.kube/config
$ az aks get-credentials -g aztest -n aztest --admin
Merged "aztest" as current context in /Users/matt/.kube/config
$ kubectl config get-contexts
CURRENT   NAME      CLUSTER   AUTHINFO                     NAMESPACE
*         aztest    aztest    clusterAdmin_aztest_aztest

After:

$ git checkout rename-admin-k8s-config
Switched to branch 'rename-admin-k8s-config'
$ rm -f ~/.kube/config
$ az aks get-credentials -g aztest -n aztest
Merged "aztest" as current context in /Users/matt/.kube/config
$ az aks get-credentials -g aztest -n aztest --admin
Merged "aztest-admin" as current context in /Users/matt/.kube/config
$ kubectl config get-contexts
CURRENT   NAME           CLUSTER   AUTHINFO                     NAMESPACE
          aztest         aztest    clusterUser_aztest_aztest    
*         aztest-admin   aztest    clusterAdmin_aztest_aztest 

cc: @slack

---

• The PR has modified HISTORY.rst describing any customer-facing, functional changes. Note that this does not include changes only to help content. (see Modifying change log).

• I adhere to the Command Guidelines.

[codecov-io]

Codecov Report

Merging #6529 into dev will not change coverage.
The diff coverage is n/a.

@@         Coverage Diff         @@
##           dev   #6529   +/-   ##
===================================
  Coverage    0%      0%           
===================================
  Files       11      11           
  Lines      133     133           
  Branches     9       9           
===================================
  Misses     133     133

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 4ce769a...a463c37. Read the comment docs.

[mboersma]

Given #6497 I assume I'll have to update HISTORY.rst in this PR before it can be merged.

[troydai]

Shouldn't the try catch in the loop instead of out of the loop?

[mboersma]

Yes indeed.

[mboersma]

Rebased to fix merge conflict.

[troydai]

Ok. I'll merge it now.