RUBY-3588 Deprecate Support for Server Version 4.0

[jamis]

Adds wire version 7 (MongoDB 4.0) to the deprecated list.

[Copilot]

Pull request overview

This PR introduces a deprecation mechanism for specific server wire versions and starts emitting deprecation warnings when connecting to servers using deprecated wire versions. It also exposes a reusable Mongo::Deprecations module and wires it into feature support checks.

Changes:

• Added Mongo::Deprecations module to centralize thread-safe, once-per-feature deprecation logging.
• Extended Mongo::Server::Description::Features#check_driver_support! to warn when the server’s max wire version is in DEPRECATED_WIRE_VERSIONS, and defined DEPRECATED_WIRE_VERSIONS = 6..7.
• Updated the feature spec to assert deprecation warnings are emitted and to verify that wire versions 6 and 7 are considered deprecated.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
spec/mongo/server/description/features_spec.rb	Adds tests verifying that check_driver_support! triggers a deprecation warning for deprecated max wire versions and that wire versions 6 and 7 are marked as deprecated.
lib/mongo/server/description/features.rb	Introduces deprecation messaging/constants, validates deprecated wire versions against supported versions, and emits deprecation warnings on connection when appropriate.
lib/mongo/deprecations.rb	New module encapsulating deprecation warning behavior with mutex-protected state and logging via Mongo::Loggable.
lib/mongo.rb	Requires the new mongo/deprecations module so it is available throughout the driver.

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