[MOENGAGE] Add support for cluster option in MoEngage SDK initialization

[janizde]

What does this PR do?

This PR adds a new option cluster that is supported by the MoEngage SDK. This option is necessary when the account is hosted in a different data center on the MoEngage side. When omitting, it will assume that the account is in data center 1 which is not always the case.

The cluster option is documented in the Data Redirection section of the MoEngage SDK documentation

Are there breaking changes in this PR?

No, when omitted the SDK will use the default like before

Testing

Testing completed successfully

1. Added option cluster to unit tests
2. Could verify functionality linking the changed package into application

Any background context you want to provide?

Is there parity with the server-side/android/iOS integration components (if applicable)?

Does this require a new integration setting? If so, please explain how the new setting works

Links to helpful docs and other external resources

1. MoEngage Web SDK Documentation on Data Redirection