Merged PR 1057: Indexer Service Unified Pipeline

* [YES] Have you followed our code review [guidelines](https://github.com/microsoft/code-with-engineering-playbook/blob/master/pull-requests/code-reviews/readme.md)?
* [YES] Have you added an explanation of what your changes do and why you'd like us to include them?
* [NO] I have updated the documentation accordingly.
* [N/A] I have added tests to cover my changes.
* [YES] All new and existing tests passed.
* [YES] My code follows the code style of this project.
* [YES] I ran lint checks locally prior to submission.

## What is the current behavior?
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1.) Currently, Azure has one build pipeline that generates the SNAPSHOT jar file for the indexer service, runs the unit tests and publishes the artifact to TFS. There's another release pipeline that was manually created in ADO that's responsible for deploying the snapshot jar to the indexer app service, generating the test core and azure indexer provider libraries and running the integration tests.

If the snapshot version were to change, the deployment operator will have to manually go into the azure portal and update the startup command for the indexer service and point the service to the new jar location.

The current pipeline is error prone as it relies on the manual update in the azure portal. The other challenge is that the current release pipeline cannot be constructed through code and/or in a repeatable fashion.

2.) Previous releases depended on cached core dependencies within the dps build agent pool.

Issue: #1291

## What is the new behavior? Why?
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1.) We've merged the build and release stages into a single pipeline by leveraging the service ADO pipeline templates within the infrastructure-templates repo.

There will be only 1 azure pipeline that is pushed through release environments based on whether a feature-branch/PR (devint) or master (devint, qa, prod) triggered the pipeline. `Opendes/os-indexer-azure` will be renamed as `Opendes/os-indexer-azure-release`.

2.) Releases no longer depend on cached dependencies as the pom.xml files now have the proper xml tags to pull down core dependencies within a non-custom microsoft hosted build agent pool.

## NEXT STEPS
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Cleanup old pipelines in task #1336. See this task for clean-up strategy

## Does this introduce a breaking change?
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- [NO]

## Pipeline Run Status for `os-indexer-azure-unified-dexterw` (feature branch using current shared pipeline)
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![image (2).png](https://dev.azure.com/slb-des-ext-collaboration/9bf2f6e3-4cfe-416c-80df-404767279175/_apis/git/repositories/a7834790-3b26-4e40-b7e7-46f5b9b34669/pullRequests/1050/attachments/image%20(2).png)

Related work items: #1291