fix(skus): Add indexes for externalID and radomSubscriptionId in orders table

[mschfh]

Summary

Improve order lookup performance by adding indexes for externalID and radomSubscriptionId metadata fields.

Type of Change

• Product feature
• Bug fix
• Performance improvement
• Refactor
• Other

Tested Environments

• Development
• Staging
• Production

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[clD11]

@mschfh you need to update the migration version here to match the newly added migration files or the migration wont run.

Also, I assume you will also run the migrations manually prior to deployment particularly for prod. For existing tables the migration/deployment will fail due to a timeout if it takes a long time to complete. For lower environments this may not be an issue but for prod this will certainly need to be run manually first.