fix tests; make tests reproducable

[RobertBorg]

PR contains the following

• Two bug fixes when using wasm-bindgen with nodejs option.
• Switching the projects internal package manager to npm as running yarn in examples directories caused yarn to recursivley cache project -> examples -> project -> ... until it had eaten up my ~ 70GB free space
• Bumped jest timeouts to 10 mins
• Locked down versions of all dependencies

I might've missed something but hopefully we can have reliable ci moving forward

[dflemstr]

It's unfortunate that we need to use npm instead of yarn but the benefits clearly outweigh! Thanks for doing these changes!

[RobertBorg]

Agreed. I'll try to revisit the issue when i get time.