fix: docs anchors

[github-actions[bot]]

Visit the preview URL for this PR (updated for commit fe20966):

• https://zksync-web-docs--v-refs-pull-278-merge-fd8r0eby.web.app
• https://staging-docs-zksync--v-refs-pull-278-merge-tsmeltld.web.app

_{(expires Thu, 19 May 2022 12:17:03 GMT)}

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