CCM-981

Periodically this step in the pipeline will fail - this
requires APIM producers to have to press the retry button
in order to get a successful build. The manual retry process
is normally successful after only 1 retry.

The error thrown here is a 401 - this makes me believe that
token created within the `Get Apigee Access Token` step was
failing.

`jq` is being used to extract the .access_token path from
the JSON response - previously it was not returning an error
code when the payload did not contain the path. This updates
the `jq` call with the `-e` flag which will error when
`.access_token` is not within the response.

An automated retry mechanism for when this error occurs has
been added to this step. It uses the built in azure devops
retryCountOnTaskFailure which will automatically back off
on subsequent failures.

See https://learn.microsoft.com/en-us/azure/devops/pipelines/process/tasks?view=azure-devops&tabs=yaml#number-of-retries-if-task-failed

Author: Philip Skinner

azure/components/get-access-token.yml

@@ -22,12 +22,15 @@ steps:
 
   - bash: |
       set -euo pipefail
+
+      # fetch the access token
       curl -X POST https://${{ parameters._auth_server[parameters.apigee_organization] }}/oauth/token \
         -H "Content-Type: application/x-www-form-urlencoded" \
         -H "Accept: application/json;charset=utf-8" \
         -H "Authorization: Basic ZWRnZWNsaTplZGdlY2xpc2VjcmV0" \
-        -d "username=${{ parameters.apigee_username }}&password=${{ parameters.apigee_password }}&mfa_token=$(secret.MFACode)&grant_type=password" | jq .access_token > .token
+        -d "username=${{ parameters.apigee_username }}&password=${{ parameters.apigee_password }}&mfa_token=$(secret.MFACode)&grant_type=password" | jq -e .access_token > .token
 
       # Set token into variable
       echo "##vso[task.setvariable variable=secret.AccessToken;issecret=true]`cat .token`"
     displayName: 'Get Apigee Access Token'
+    retryCountOnTaskFailure: 5