fix(graphcache): Remove `for-of` syntax from Graphcache code for JSC memory reduction

[kitten]

[!NOTE] I'll have to look into the bundlesize impact. Currently, this seems to have an outsized impact of 0.13kB minzipped, which seems a little high for what this is doing.

[changeset-bot[bot]]

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Latest commit: 1eb45cc3900eaf43d49f8bdc1cd2fd5580cb207c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@urql/exchange-graphcache	Patch

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