Remove CSP values that were added for removed GKE feature

What does this MR do and why?

Fixes https://gitlab.com/gitlab-org/gitlab/-/issues/336139

Since the removal of the form-based GKE creation page in #357309 (closed) there are some values in the CSP that aren't needed anymore. This MR removes them.

They were originally added to the .com GSP in this commit https://gitlab.com/gitlab-com/gl-infra/chef-repo/-/commit/f04a64a06706be6fd7fd0762a3291aa8c621f3e0 and then added to the Rails-based CSP because we simply copied the values over from .com.

Screenshots or screen recordings

N/A

How to set up and validate locally

Once the GDK is up and running run this command

$ curl -si http://gdk.test:3000/ | grep -i content-security-policy
Content-Security-Policy: base-uri 'self'; child-src https://www.google.com/recaptcha/ https://www.recaptcha.net/ https://www.googletagmanager.com/ns.html http://gdk.test:3000/rails/letter_opener/ http://gdk.test:3000/admin/ http://gdk.test:3000/assets/ http://gdk.test:3000/-/speedscope/index.html http://gdk.test:3000/-/sandbox/ https://customers.staging.gitlab.com http://gdk.test:3000/assets/ blob: data:; connect-src 'self' http://gdk.test:3808 ws://gdk.test:3808 http://gdk.test:9091/ ws://gdk.test:3000 test.local; default-src 'self'; font-src 'self'; form-action 'self' https: http:; frame-ancestors 'self'; frame-src https://www.google.com/recaptcha/ https://www.recaptcha.net/ https://www.googletagmanager.com/ns.html http://gdk.test:3000/rails/letter_opener/ http://gdk.test:3000/admin/ http://gdk.test:3000/assets/ http://gdk.test:3000/-/speedscope/index.html http://gdk.test:3000/-/sandbox/ https://customers.staging.gitlab.com; img-src 'self' data: blob: http: https:; manifest-src 'self'; media-src 'self' data: blob: http: https:; object-src 'none'; script-src 'strict-dynamic' 'self' 'unsafe-inline' 'unsafe-eval' https://www.google.com/recaptcha/ https://www.recaptcha.net 'nonce-zAFZIJHR5c4lmI0UXmYwGQ=='; style-src 'self' 'unsafe-inline'; worker-src http://gdk.test:3000/assets/ blob: data:

and observe that the values that were removed in this MR do not appear in the CSP

MR acceptance checklist

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