fix: Ensure DirectX capturer is supported

[ckerr]

Manual backport of #13543

I don't even know yet if this builds on Windows and usually wouldn't do a premature PR like this; however since time is a factor for 2.1.0 and I'm about to EOD, this is here if someone wants to take the baton and run with it.

@ajmacd @MarshallOfSound

[ckerr]

Both CI failures are

not ok 47 app module mixed sandbox option when app.enableMixedSandbox() is called adds --enable-sandbox to render processes created with sandbox: true
  Error: Timeout of 30000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves.
      at C:\projects\electron\spec\node_modules\mocha\lib\runnable.js:232:19
not ok 48 app module mixed sandbox option when the app is launched with --enable-mixed-sandbox adds --enable-sandbox to render processes created with sandbox: true
  Error: Timeout of 30000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves.

which is the mixed-sandbox issue discussed at #13769 and #13770 and I think can be disregarded here