Multiple WS urls for PolkadotJS API

[ekenigs]

Description

Closes #231

Checklist

• If this requires a documentation change, I have created a PR in moonbeam-docs repository.
• If this requires it, I have updated the Readme
• If necessary, I have updated the examples
• I have verified if I need to create/update unit tests
• I have verified if I need to create/update acceptance tests
• If necessary, I have run acceptance tests on this branch in CI

[changeset-bot]

🦋 Changeset detected

Latest commit: 41ce806

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

This PR includes changesets to release 5 packages

Name	Type
@moonbeam-network/xcm-types	Patch
@moonbeam-network/xcm-utils	Patch
@moonbeam-network/xcm-builder	Patch
@moonbeam-network/xcm-config	Patch
@moonbeam-network/xcm-sdk	Patch

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