Remove CGO dependencies

[johanbrandhorst]

https://github.com/ServiceWeaver/weaver/issues/79 reported an issue building on MacOS, which was resolved by explicitly documenting installation instructions. However, during the discussion, the idea of removing the sqlite CGO depencency was raised. I would like to revive this discussion as I believe there are many reasons to remove any CGO dependencies in a Go project including:

• Trivial cross compilation
• Higher performance
• Fewer build dependencies
• Fewer build headaches for users (I'm here because I had a distinct CGO build error from the one in #79).

Please replace the CGO sqlite driver with the CGO free one from https://pkg.go.dev/modernc.org/sqlite.

[breml]

@johanbrandhorst thanks for raising this.

After #79 has been closed by updating the documentation, I also returned to this issue for the exact same arguments already mentioned above.

[spetrovic77]

Thanks for reporting, see the attached pull request.