Use process.versions.node to check for Node.js environment and increase timeout for Chrome workflow.

[elliotwutingfeng]

• Prevents PlatformWeb from loading entropy source from null on Node.
• Node.js / Browser detection no longer relies on try/catch; replaced with null check for JavaScript process.versions.node. If it is not null, it is Node, otherwise it is probably a web browser.
• Increase timeout to 2x for Chrome tests as the default timeout is insufficient.
• Implementation no longer depends on js_interop_unsafe

Closes #257