ci: update ESRP code signing to v6

[Vincent Biret (baywet)]

Summary

• Update ESRP code signing pipeline tasks from v5 to v6.
• Use the short EsrpCodeSigning@6 task name in ESRP templates.

Notes

ESRP code signing v5 runs on Node16 and is getting deprecated, so this moves the pipelines to v6.

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[learn-build-service-prod]

Learn Build status updates of commit e537494:

❌ Validation status: errors

Please follow instructions here which may help to resolve issue.

File	Status	Preview URL	Details
	❌Error		Details

• Line 0, Column 0: [Error: PSMD2Yaml_FileLoadFailed] Failed to load file: C:/LocalRun/W/ghvu-s/module/mapping/monikerMapping.json. PackageRoot, ReferenceTocUrl, and ConceptualTocUrl are required for every moniker. PackageRoot should be a valid relative path to docset root.

For more details, please refer to the build report.

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