Admin UI baseHref

[michaelbromley]

Discussed in #992

^{Originally posted by BenVuti July 15, 2021}
When trying to locally setup the compiling-as-a-deployment-step I ran into the issue of the /admin page being blank.

I tried modifying the <base href="/" /> to <base href="/admin" /> in the index.html file but it didn't fix the problem.

I then deleted the entire admin-ui folder, added the following line to the compileUiExtensions

compileUiExtensions({
    outputPath: path.join(__dirname, 'admin-ui'),
    baseHref: '/admin', // <----
    extensions: [/* ... */],
}).compile?.().then(() => {
    process.exit(0);
});

I rebuilt and tried to access the admin again, but the page remained blank.
By inspecting the source code of the page I can see that the baseHref is still "/"

[michaelbromley]

I think this relates to #916