Don't write locks if both the locks and props change

[FinlayRJW]

Before this PR

Issue #47 outlined how changing branch triggered a write lock if both props and locks where different

After this PR

We now track both props and locks changes and only trigger locks writes if the locks file has not changed within 350ms of the props file changing

This was slightly more complex than expected as the events that prepareChange are batched so you cannot guarantee that the change to props and locks will be in the same call to prepareChange so you must track state

==COMMIT_MSG==
Don't write locks if both the locks and props change
==COMMIT_MSG==

Possible downsides?

This could prevent intentional locks writing if the props and locks change within 350ms of one another

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• improvement: An incremental improvement in the functionality or operation of the service.
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Type

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• Improvement
• Fix
• Break
• Deprecation
• Manual task
• Migration

Description

Don't write locks if both the locks and props change

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[CRogers]

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