disable `deno upgrade` about pantry.core

[zegl]

Hey!

A good start to fixing this issue could be to disable the self-upgrade notification message. This can be done by setting the DENO_NO_UPDATE_CHECK env var (ref). It doesn't prevent upgrades, but it might stop the temptation of users to upgrade deno in a non-tea way.

I'll send a PR soon that adds an option to package.yml to set runtime env vars. I'd imagine that many similar self-upgradeable tools have some way of disabling self upgrade either through runtime configs or compile time flags. Unfortunately deno does not provide a way to do it at compile-time.

To prevent upgrades over all, using sandbox-exec (pkgxdev/pkgx#77) sounds like a good idea.

[mxcl]

To prevent upgrades over all, using sandbox-exec (pkgxdev/pkgx#77) sounds like a good idea.

Ah yes, I see why you did #77 like you did now.

We could still do this, just we may have to allow writes to certain parts of TEA_PREFIX, eg. tmp or var.

Definitely I would love to do this if we can without it being more hassle than it is worth.