Improve management test coverage

[bart-vmware]

Description

This PR improves test coverage of the Steeltoe actuator endpoints by running tests against host builders and asserting on full JSON response bodies. While doing so, several bugs were fixed.

Related PR to update the documentation can be found at SteeltoeOSS/Documentation#386.

cloudfoundryapplication endpoint

Refactor tests for cloudfoundryapplication endpoint

• Order the returned list of endpoints by ID
• Critical fix: block /cloudfoundryapplication and log warning when security middleware not added
• Critical fix: don't turn off all security when the /cloudfoundryapplication hypermedia endpoint is turned off

dbmigrations endpoint

Refactor tests for dbmigrations endpoint

env endpoint

Refactor tests for env endpoint

• Only display changed values from placeholder/decryption providers
• Show placeholder/decryption providers after the configuration providers they wrap
• Hide providers that don't have any properties (reverted for Spring Boot compatibility)

health endpoint

Refactor tests for health endpoint

• Order health check results in descending status
• Simplify test health contributors (single purpose)
• Refactor tests for health contributors, move availability contributors to matching namespace
• Add internal file system abstraction for testability of disk space contributor
• Remove duplicate information in details for ASP.NET health checks
• Fixed: X-Use-Status-Code-From-Response header not always respected
• Fixed inconsistency in case-sensitivity of health group names

heapdump endpoint

Refactor tests for heapdump endpoint

threaddump endpoint

Refactor tests for threaddump endpoint

httpexchanges endpoint

Refactor tests for httpexchanges endpoint

• Replace IHttpExchangesRepository with IHttpExchangeRecorder, so that filtering logic becomes testable
• Fixed: appsettings.json files from RazorPagesTestApp were still being copied by VS Build Acceleration
• Fixed: options.IncludeTimeTaken was ignored
• Move HttpExchanges into MemoryDumps category
• Reduce pressure when running all tests locally, so that DiagnosticObserverHttpExchangeRecorder doesn't fail

hypermedia endpoint

Refactor tests for hypermedia endpoint

• Order the returned list of endpoints by ID
• Fixed: The value returned for "templated" was always false

info endpoint

Refactor tests for info endpoint

• Fixed: adjust contributor nullability to allow null dictionary values
• Fixed: do not skip lines in git.properties file that contain = character in their value

loggers endpoint

Refactor tests for loggers endpoint

refresh endpoint

Refactor tests for refresh endpoint

• Fixed: order keys alphabetically, without duplicates
• Fixed: throw when unable to reload, instead of silently do nothing

mappings endpoint

Refactor tests for mappings endpoint

beans endpoint

Refactor tests for beans endpoint

all endpoints

• Refactor tests for all actuators

Spring Boot Admin

• Add tests for Spring Boot Admin

Other

• Revise tests for dependent services: get middleware instance to ensure all downstream dependencies are registered
• Simplify tests for options: there's no added value in using host builders
• Cleanup tests for management/endpoint options
  • Fixed: allow clearing default exposure using Spring-style configuration keys
  • Fixed: remove duplicate entries in exposure over regular and Spring-style keys
• Move content negotation tests for SBA
• Adapt configuration key names to .NET naming convention, inline constants

Fixes #1028.

Quality checklist

• Your code complies with our Coding Style.
• You've updated unit and/or integration tests for your change, where applicable.
• You've updated documentation for your change, where applicable.
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[TimHess]

Generally LGTM, just a couple small items that could be addressed