[fix/photouploadcrash] Fix automatic photo upload crash on iOS 15

[felix-schwarz]

Description

On iOS 15, automatic photo upload seems to consume more resources than are available, leading to a crash. This pull requests reduces the number of concurrent photo upload operations from available cores to 1.

Related Issue

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

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[jesmrec]

This one is related with performance and not easy to reproduce. I'd move it forward and wait for feedback in case the problem persist. What do you think?

[hosy]

@jesmrec yes I think this is not easy to reproduce and you can finish without further testing. Thanks!