Adds option to set publishableKey in on instance creation

[lennartzellmer]

Since this package is running on client side only, rebuilding for every change in the nuxt config or environment variable is not necessary.

Using runtimeconfig would be the better way to provide the publishableKey to the getStripeInstance function
https://nuxtjs.org/docs/2.x/directory-structure/nuxt-config#runtimeconfig

I have the feeling that having a factory function for getStripeInstance would be a bit cleaner, but I am not able to get the type configuration working =/

After my changes, I am using it like this:
const stripe = await $stripe(undefined, $config.stripe.publishableKey)

[fabiofdsantos]

@lennartzellmer, thanks for your PR!

The plugin.ts already contains the context, which means you can access the "runtime config" via ctx.$config:

nuxt-stripejs/lib/plugin.ts

Line 47 in 4d6e21f

const stripePlugin: Plugin = (ctx, inject): void => {

I understand your point but we need to find a clean way to support "runtime config".

[fabiofdsantos]

I've introduced support to runtime configuration 👍🏻