docs(storage): minor fix

[vaibhavhrt]

replace storage with storage() in example

Summary

Checklist

• Supports Android
• Supports iOS
• e2e tests added or updated in packages/**/e2e
• Flow types updated
• Typescript types updated

Test Plan

Release Plan

[DOCS][BUGFIX] [Storage] - Minor fix in doc of cloud storage

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[CLAassistant]

All committers have signed the CLA.

[vaibhavhrt]

Will check this doc page once more to check if anything else can be fixed and will sign this CLA thing, then will mark this ready for review.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@7f52366). Click here to learn what that means.
The diff coverage is n/a.

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[vaibhavhrt]

This PR is ready for review now, one test is failing but I don't think it's related to changes I did.

[vaibhavhrt]

opps clicky fingers