Fixing how `define` are applied by wrangler

[vicb]

The wrangler configuration has defines that should be applied by ESBuild bundling:

However they are only applied when process.env.NODE_ENV is defined at build time:

workers-sdk/packages/wrangler/src/deployment-bundle/bundle.ts

Lines 386 to 396 in 7d0417b

	...(process.env.NODE_ENV && {
	define: {
	...(defineNavigatorUserAgent
	? { "navigator.userAgent": `"Cloudflare-Workers"` }
	: {}),
	// use process.env["NODE_ENV" + ""] so that esbuild doesn't replace it
	// when we do a build of wrangler. (re: https://github.com/cloudflare/workers-sdk/issues/1477)
	"process.env.NODE_ENV": `"${process.env["NODE_ENV" + ""]}"`,
	...define,
	},
	}),

That is process.env.NODE_ENV && gates too many values.

This was fixed in #7932 and further reverted in #7967 because the initial PR lacks tests.

We should re-introduce the initial PR with tests

[vicb]

To add to that, the code snippet of the PR description is compiled as (in wrangler-dist/cli.js):

    ...{
      define: {
        ...defineNavigatorUserAgent ? { "navigator.userAgent": `"Cloudflare-Workers"` } : {},
        // use process.env["NODE_ENV" + ""] so that esbuild doesn't replace it
        // when we do a build of wrangler. (re: https://github.com/cloudflare/workers-sdk/issues/1477)
        "process.env.NODE_ENV": `"${process.env["NODE_ENV"]}"`,
        ...define
      }
    },

That's because ESBuild will evaluate process.env.NODE_ENV && as true && when bundling wrangler