feat(nextjs): Add options to disable webpack plugin

[lobsterkatie]

Despite our strong encouragement, not everyone wants to use the SentryWebpackPlugin to upload sourcemaps. This PR introduces two new options, disableServerWebpackPlugin and disableClientWebpackPlugin, which can be used in next.config.js like this:

const { withSentryConfig } = require("@sentry/nextjs");

const moduleExports = {
  sentry: {
    disableServerWebpackPlugin: true,
    disableClientWebpackPlugin: true,
  },
};

// unnecessary if the webpack plugin is disabled for both server and client (in that case, can also safely 
// be omitted from the `withSentryConfig` call below)
const SentryWebpackPluginOptions = {
  // ...
};

module.exports = withSentryConfig(moduleExports, SentryWebpackPluginOptions);

Setting either of these options does two things in the relevant (server or client) config:

• prevents the SDK from forcing webpack.devtool to be source-map in production, and
• prevents the SDK from adding an instance of SentryWebpackPlugin to the webpack config.

These changes are documented in getsentry/sentry-docs#3826.

Fixes #3674
Fixes #3513
Fixes #3553
Fixes #3737

[github-actions]

size-limit report

Path	Size
@sentry/browser - CDN Bundle (gzipped)	21.39 KB (+0.01% 🔺)
@sentry/browser - Webpack	22.4 KB (0%)
@sentry/react - Webpack	22.44 KB (0%)
@sentry/browser + @sentry/tracing - CDN Bundle (gzipped)	28.89 KB (0%)

[AbhiPrasad]

Taking some time to think about this, the tests for constructWebpackConfigFunction should just be a table test, where we pass in different permutations of the config and assert on the return value. We can do this in another PR though.

[AbhiPrasad]

Reminder: We need to add a task to add this new option to the docs.

[lobsterkatie]

Reminder: We need to add a task to add this new option to the docs.

Precisely why It's still in draft mode! 🙂

NB: In draft form only because

• it needs to be rebased once ref(nextjs): Pre-disable-plugin-option config cleanup #3770 is merged, and
• these options need to be documented.