Consider releasing 5.2.0 stable

[tagliala]

Hello,

Recently, shakapacker 9.0 added this library to its requirement, and I'm seeing this imported as

 "webpack-subresource-integrity": "5.2.0-rc.1"

Since this is in RC since a couple of years, could you please consider a 5.2.0 stable release?

Thanks!

[pieterocp]

There's been a few commits to master (6 at the time of writing v5.2.0-rc.1...main) + a couple of open issues too so this might be sensible to resolve those before this.