chore: remove SAP registry from readme

[mbtools]

The SAP npm registry has been retired:
https://help.sap.com/docs/SAP_HANA_PLATFORM/4505d0bdaf4948449b7f7379d24d0f0d/726e5d41462c4eb29eaa6cc83ff41e84.html

[changeset-bot]

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Latest commit: 1afcd7a

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