Add a test on the providers settings

[brichet]

After #113, the providers settings won't be checked anymore against the typescript interface, and won't be automatically generated.

We should find a way to test that these settings are still relevant with the current version of the providers, to make sure that a provider won't be broken after an update.

[brichet]

One way to test it could be to generate a script and try to build it.
This script could generate an object with default value from the setting schema, and try to instantiate a model with it.

For example if I try to build the following script, it fails:

import { ChatMistralAI } from '@langchain/mistralai';

const settings = { fakeSettings: 'anything' };
const model = new ChatMistralAI(settings);

$ npx tsc scripts/test.ts 
scripts/test.ts:4:33 - error TS2559: Type '{ fakeSettings: string; }' has no properties in common with type 'ChatMistralAIInput'.

4 const model = new ChatMistralAI(settings);
                                  ~~~~~~~~


Found 1 error in scripts/test.ts:4

[brichet]

One way to test it could be to generate a script and try to build it.

For the record, I tried this but it doesn't work, it builds as soon as the required settings are provided.
Therefore, it doesn't test if some settings are unused, it would probably only ensure that the required settings are provided.