Rclone: don't rely on cached bandwidth limit in configguard

[Michal-Leszczynski]

This PR fixes the way in which configguard checked if bandwidth limit should be updated.
Previously it was updating bandwidth limit with each Rclone call, now it updates it only when it's changed.

This PR also removes unnecessary usages of RcloneSetBandwidthLimit, as handling bandwidth limit should be done by specific Rclone calls.

Fixes #4119

[Michal-Leszczynski]

Example agent logs from TestRestoreFullIntegration before the change:

{"L":"INFO","T":"2024-11-22T10:52:47.258Z","N":"rclone","M":"Bandwidth limit reset to unlimited"}
{"L":"INFO","T":"2024-11-22T10:52:57.568Z","N":"rclone","M":"Bandwidth limit reset to unlimited"}
{"L":"INFO","T":"2024-11-22T10:53:07.829Z","N":"rclone","M":"Bandwidth limit reset to unlimited"}
{"L":"INFO","T":"2024-11-22T10:53:17.901Z","N":"rclone","M":"Bandwidth limit reset to unlimited"}

And after the change:

{"L":"INFO","T":"2024-11-22T10:46:50.445Z","N":"rclone","M":"Bandwidth limit set to {999M 999M}"}

(changed bandwidth limit to 999M because otherwise we wouldn't see any log with bandwidth limit change, but that's expected)

[Michal-Leszczynski]

TestPurgeIntegration failed, but it looks flaky and not related to this PR, but I will try to investigate it.

[Michal-Leszczynski]

TestPurgeIntegration failed, but it looks flaky and not related to this PR, but I will try to investigate it.

No luck with that - there is some chance that minio lagged when listing manifests just after their creation.

[VAveryanov8]

LGTM

[Michal-Leszczynski]

@karol-kokoszka The PR is ready for review!

[Michal-Leszczynski]

@karol-kokoszka This PR is ready for review! Let's merge it and start the 3.4.1 release process.