[Account Storage Maps] Add return value to account migration scheduling functions

[turbolent]

Work towards #3584

Description

Add a return value to the functions which allow scheduling the migration of accounts.

We need this value in the system contract which will call the function to know if the V2 storage format is enabled, and the migration can be performed.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:feature/combine-domain-payloads-and-domain-storage-maps commit caaf254
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -benchmem -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Collapsed results for better readability