Remove Woodstox from WAR

[basil]

The tasks in #5604 (comment) have been completed, so #5604 can be reverted:

• Use of non-Stax2-compatible Stax2 implementation fails when reading from byte[] FasterXML/jackson-dataformat-xml#482 was released in 2.12.4
• Bump Jackson from 2.12.3 to 2.12.4 jackson2-api-plugin#84 was released in 2.12.4
• Use Jackson 2 API plugin for XML parsing azure-sdk-plugin#26 was released in 25.vcde945b30f00
• Bump jackson2-api from 2.12.3 to 2.12.4 bom#581 was released in 909.vf028101f1bfa
• BOM now includes jackson2-api 2.12.4 azure-sdk-plugin#31 was released in 30.vf3165534d6e8
• Use released versions of jenkinsci/bom#581 and jenkinsci/azure-sdk-plugin#31 azure-storage-plugin#196 was released in 359.v09573e5ff73f
• Use released versions of jenkinsci/bom#581, jenkinsci/azure-sdk-plugin#31, and jenkinsci/azure-storage-plugin#196 azure-container-agents-plugin#83 was released in 210.v8071dd1c9f3f
• Use released versions of jenkinsci/bom#581 and jenkinsci/azure-storage-plugin#196 azure-artifact-manager-plugin#23 was released in 93.v9bc4e012ba4d

Testing done

• Ran java -jar jenkins.war and installed the default plugin list and the Azure Storage plugin.
• Started the Azurite storage emulator with docker run -p 10000:10000 -p 10001:10001 -p 10002:10002 mcr.microsoft.com/azure-storage/azurite.
• Went to http://127.0.0.1:8080/credentials/store/system/domain/_/newCredentials and added a new Azure Storage credential with account name, devstoreaccount1, account key Eby8vdM02xNOcqFlqUwJPLlmEtlCDXJ1OUzFT50uSRZ6IFsuFq2UVErCz4I6tq/K1SZFPTOtr/KBHBeksoGMGw==, and URL http://127.0.0.1:10000/devstoreaccount1/.
• Clicked Verify Configuration and confirmed that the "Validation successful" message was printed.

Proposed changelog entries

Removed: The Woodstox implementation of the StAX API has been removed from Jenkins core. Users of the Azure Artifact Manager, Azure Container Agents, Azure Storage, and Azure SDK API plugins must upgrade those plugins to the latest versions in lockstep with this core upgrade. Plugins that consume Woodstox should depend on it directly or via the Jackson 2 API plugin.

Proposed upgrade guidelines

The Woodstox implementation of the StAX API has been removed from Jenkins core. Users of the Azure Artifact Manager, Azure Container Agents, Azure Storage, and Azure SDK API plugins must upgrade those plugins to the latest versions in lockstep with this core upgrade. Plugins that consume Woodstox should depend on it directly or via the Jackson 2 API plugin.

Submitter checklist

• (If applicable) Jira issue is well described
• Changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developer, depending on the change). Examples
  • Fill-in the Proposed changelog entries section only if there are breaking changes or other changes which may require extra steps from users during the upgrade
• Appropriate autotests or explanation to why this change has no tests
• For dependency updates: links to external changelogs and, if possible, full diffs

Desired reviewers

@mention

Maintainer checklist

Before the changes are marked as ready-for-merge:

• There are at least 2 approvals for the pull request and no outstanding requests for change
• Conversations in the pull request are over OR it is explicit that a reviewer does not block the change
• Changelog entries in the PR title and/or Proposed changelog entries are correct
• Proper changelog labels are set so that the changelog can be generated automatically
• If the change needs additional upgrade steps from users, upgrade-guide-needed label is set and there is a Proposed upgrade guidelines section in the PR title. (example)
• If it would make sense to backport the change to LTS, a Jira issue must exist, be a Bug or Improvement, and be labeled as lts-candidate to be considered (see query).

[daniel-beck]

Looks reasonable, thanks for taking care of this 👍

I suggest the changelog entry be rephrased, instead of

the latest versions in lockstep

it should specify the versions to use to make it easier to confirm you're on what's needed; especially once it's a few weeks later and newer (but unnecessary) plugin releases are out.

[oleg-nenashev]

No objections from me. Time to start the countdown?

[timja]

This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!