Fix jsbn browser check

[bolt-juri-gavshin]

fixes #1081

Previous versions of NodeJS/Bun/Deno didn't have 'navigator' defined, while latest one do have it, which forces am2 algorithm with 26 dbits, which is awfully slow (~20x), at least in NodeJS v22 (compared to am3 with 28 dbits)

[bolt-juri-gavshin]

@davidlehn this PR is an alternative to the PR by @dhensby
Without the fix, upgrading from NodeJS v20 to v22 (LTS since end of 2024) requires nasty workarounds with global navigator (to continue performing).
Is it possible to get v1.3.2 with either of the fixes? Mine should cover other runtimes as well, but other one is also ok, as I care only about NodeJS :)

[dhensby]

This feels like a bad idea, appName is deprecated, so liable to be removed from browsers - meaning that it could cause unintended behaviour in browsers.

Also, we're still coupling with the navigator global and could still cause problems in the future if node/bun/deno/etc decide to populate this new property we now rely on to be undefined. The utils.isNode is specifically designed to determine if we are running in a node context, and thus makes more sense as a single-point-of-truth for this information and feature toggling.

[bolt-juri-gavshin]

Thanks for the comment, I will close my PR then.
Is there a chance for the #1082 to be merged/released any time soon?