Update DiskArrays dependency to 0.4

[meggart]

The whole indexing pipeline was reformulated in DiskArrays 0.4 fixing many bugs for strange vector indexing patterns. In addition this will finally make all types of getindex calls type stable.

This is not ready to merge yet since Zarr tests revealed one upstream bug.

[felixcremer]

Could this be merged now that the upstream bug is fixed and released in DiskArrays 0.4.2?
I tested locally with DiskArrays 0.4.2 and didn't see the error anymore but have reported #144 but this also happens with DiskArrays 0.3 and seems to be independent.

[github-actions]

Pull Request Test Coverage Report for Build 8783611095

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-2.5%) to 85.946%

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Totals
Change from base Build 8519573721:	-2.5%
Covered Lines:	795
Relevant Lines:	925

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