Add Seals to BlockPayload

[beaugunderson]

Closes: #148

Description

Implements the Seals property of BlockPayload using the technique used for CollectionGuarantees as a guide.

Some context on Discord.

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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.
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[psiemens]

Hey @beaugunderson, thanks for adding this!

I added a comment about tests, but the code itself looks great 👍

Also, can you run gofmt and push the changes? Looks like some of the indentation is off in a few places

[beaugunderson]

@psiemens tests added and gofmt applied 👍

should the potential issue with the Access API be tracked somewhere btw? (the one re: this block among others not having any seals via the explorer or the flow-sdk)

[psiemens]

You can use the new BlockSeals generator here, similar to g.guarantees above.

I'd probably just add a single seal to each block:

seals := []*flow.BlockSeal{
  g.seals.New(),
}

Thanks for adding the generator, BTW!

[beaugunderson]

@psiemens great, added that (and the corresponding instantiation) 👍

[psiemens]

Looks good! Thanks again