Replace dict.update with new implementation

[inoas]

trafficstars

• rename dict.update to dict.upsert
• deprecate dict.update
• 2.0 let dict.update return Result and Error if no key found

[inoas]

Is there interset in this, then I'd create a PR.

[lpil]

Let's do it!

1. Deprecate dict.update and introduce dict.upsert
2. Remove dict.update
3. Introduce the new dict.update

[mooreryan]

Is there still any interest in a change/alter function as in #599?

[lpil]

That's what the new dict.update is to be

[inoas]

@lpil as short as possible:

1. https://github.com/gleam-lang/stdlib/issues/599 seems to be about a function that either updates or removes or adds values to a dict
2. while my PR https://github.com/gleam-lang/stdlib/pull/610 is a simple change to the old update to return a Result and simplfy the apply function at the same time.

I do not want to steal anyones opportunity here and am happy to do whatever consensus arrises or whatever the core team decides.

I like all three: the new upsert, the new update and the proposed change/alter (last has the highest complexity to use however)