Remove pkg_resources dependency on python 3

[StykMartin]

Fixes #232

[Copilot]

Pull request overview

Removes direct pkg_resources usage on Python 3 by introducing a small compatibility layer around importlib.resources / importlib.metadata, and updates call sites to use it.

Changes:

• Added bkr.common.resources module providing resource_* helpers and iter_entry_points.
• Updated schema parsing and client plugin discovery to use the new helpers instead of pkg_resources.
• Added unit tests covering the new resources helpers.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
Common/bkr/common/test_schema.py	Switches schema loading from pkg_resources.resource_stream to the new resource_stream wrapper.
Common/bkr/common/test_resources.py	Adds tests for new bkr.common.resources helpers.
Common/bkr/common/resources.py	Introduces importlib.resources / importlib.metadata wrappers to replace pkg_resources on Python 3.
Common/bkr/init.py	Adjusts namespace package handling to avoid pkg_resources on Python 3.
Client/src/bkr/client/main.py	Switches entry point discovery from pkg_resources.iter_entry_points to wrapper.
Client/src/bkr/client/commands/cmd_job_submit.py	Switches schema stream loading from pkg_resources to wrapper.
Client/src/bkr/client/init.py	Switches resource filename resolution from pkg_resources to wrapper.
Client/src/bkr/init.py	Adjusts namespace package handling to avoid pkg_resources on Python 3.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

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Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated no new comments.

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[StykMartin]

λ ./docker/dev.sh bkr-py3 system-list --host-filter DISK__SIZE_MIN_10G
Nothing Matches
λ ./docker/dev.sh bkr-py3 system-list --host-filter FAKE_FILTER
Pre-defined host-filter does not exist: FAKE_FILTER
λ ./docker/dev.sh bkr system-list --host-filter DISK__SIZE_MIN_10G
Nothing Matches
λ ./docker/dev.sh bkr system-list --host-filter FAKE_FILTER
Pre-defined host-filter does not exist: FAKE_FILTER