Adds restriction to component fetching for nested components

What does this MR do and why?

Updates component fetching

In !127448 (merged), the fetching of the components was updated by restricting the location of the component file to specific directories. However, the directory structure implemented was slightly different that the proposal that was agreed upon: &10728, which states that there are 2 cases defined by the structure:

1. a self-contained component: templates/secret-detecion.yml
2. a complex component that relies on adjacent files: templates/dast/template.yml with only one component inside - other files are ignored.

Changelog: changed

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Before	After

How to set up and validate locally

In a project that is marked as a component, create the following structure:

templates/secret-detection.yml # simple
templates/another-directory/template.yml # complex
templates/another-directory/test-template.yml # will be invalid when referenced
templates/another-directory/another-directory-2/template.yml # will be invalid when refereneced

include:
  - component: 'gdk.test:3000/root/test-project/another-directory@main' # valid complex component
  - component: 'gdk.test:3000/root/test-project/secret-detection@main' # valid simple component
  - component: 'gdk.test:3000/root/test-fetching-component/another-directory/test-template@main' # invalid
  - component: 'gdk.test:3000/root/test-fetching-component/another-directory/another-directory-2@main' # invalid

You should get an invalid error for the second component, like the screenshot above.

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