fix: retry delay not persisting between calls

[DoisKoh]

Summary

Retry delays are not actually working as specified in the docs. Currently, retry delays are not persisted between retries, resulting in exponential backoff not actually increasing the delay amount as time goes on. The linear backoff also does not currently work.

I've added a unit test for this, as well as the change for the behavior to comply with what's actually stated in the docs.

Set of changes

• Made retry delays persist in the context, allowing backoffs to work
• Added unit test for retry delay
• Modified an existing unit test that was failing (I believe it might have been incorrect, but I'm not entirely sure, please verify! It seems like the retry value is meant to reset after a retry that was successful [so, a successful operation], but the unit test was checking the retry values after a failed/errored operation instead. However, the test was passing because the retry delays were never being carried across operations anyway.)

[changeset-bot]

🦋 Changeset detected

Latest commit: 0d73b93

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-retry	Patch

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