MONGOID-5904 Use new toolchain (#6056) (#6057)

[comandeo-mongo]

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[Copilot]

Pull Request Overview

This PR migrates the project to use a new Ruby toolchain by replacing the existing Ruby environment setup with rbenv-based installation from a custom toolchain repository. The changes modernize the test infrastructure by removing Docker-based environments, updating MongoDB orchestration setup, and standardizing topology naming conventions (e.g., "standalone" → "server", "replica-set" → "replica_set").

Key changes include:

• Replaced set_env_python and set_env_ruby with direct rbenv installation from mongo-ruby-toolchain
• Added bootstrap-mongo-orchestration function and integrated it into test workflow
• Updated all topology identifiers to use underscores instead of hyphens
• Added rspec_junit_formatter dependency and JUnit XML output for test results

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
spec/shared	Updated subproject commit to newer version
gemfiles/standard.rb	Added rspec_junit_formatter gem for JUnit XML test output
.evergreen/run-tests.sh	Replaced environment setup functions with rbenv toolchain installation; removed server launch logic
.evergreen/run-tests-atlas-full.sh	Migrated to rbenv toolchain; added JUnit formatter to test output
.evergreen/config/variants.yml.erb	Updated Ruby versions, MongoDB versions, and standardized topology naming conventions
.evergreen/config/commands.yml.erb	Changed VERSION to MONGODB_VERSION; added bootstrap-mongo-orchestration function; renamed install dependencies to setup system
.evergreen/config/axes.yml.erb	Renamed VERSION to MONGODB_VERSION; updated topology IDs to use underscores; removed obsolete OS configurations
.evergreen/config.yml	Applied same configuration changes as commands.yml.erb and axes.yml.erb to generated config

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