BD-3744 Generalize mobile push page

[rachel-feinberg]

Why are you making this change? (required)

Update documentation to be more broad as this is not specifically for safari only, but includes chrome, edge, and firefox as well.

Related PRs, issues, or features (optional)

BD-3744

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• N/A

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[lydia-xie]

There's a merge conflict, but other than that lgtm!