Fix issue caused by new script cache in 1.23.1

[mfriedy]

Fixes #46

• Set script_path to absolute script path, as this seems to be more consistent with that is done normally in streamlit (and is needed for the sourcewatcher to register it correctly?)
• re-register the scriptwatcher that the scriptcache uses, to pick up the pages added by st_pages

@blackary - I am not sure how correct it is to directly interact with the runtime like this. But it seems to fix the issue :)

[mfriedy]

Hi @blackary any chance you can look at this?

[blackary]

@mfriedy Yes, sorry it's taken a while, but I will take a look at this. I've been doing some work to get tests fixed in #45

[blackary]

@mfriedy I had trouble getting the fix to work without adding a tiny sleep. After that it seemed to work fine. Now making sure it still works with different versions.

[blackary]

I can get the tests to pass locally, but am having trouble getting them to pass on github actions so far :/

[mfriedy]

That's really weird re the sleep, no idea. Is it something to do with accessing the runtime directly?

[blackary]

THANK YOU so much for this improvement -- so sorry it took so long to get everything passing