Increase time until timeout warning is shown for a custom component

[raethlein]

Close #7046

While the custom component is loaded, we show the loading skeleton. Following changes are made in this PR:

1. the warning component will be shown after 60s instead of 3s to make it less disruptive in case of slower loading times
2. after 15s, a console warning is shown in the browser's DevTools as a soft-warning for the developer
3. the warning texts are modified slightly and are now different based on whether a url is provided (usually dev mode) or not
4. the existing class component is re-written as a functional component. Since I had to touch the component anyways, I thought it's a good idea to refactor it using the newer React style and make the changes then
5. Add a couple of more tests for some convenient methods that now live in its own file componentUtils.ts
6. Add a couple of more types. As a future note: most types are also defined in the component-lib/ module and we could think about creating a shared module so that we do not duplicate the typing etc. However, I consider this to be out of scope for this PR.
7. The loading skeleton will mimic the same height if we infer from the custom component provides a height value.

Screenshot of warning messages

Screenshot of loading skeletons

Describe your changes

GitHub Issue Link (if applicable)

Testing Plan

• Explanation of why no additional tests are needed
• Unit Tests (JS and/or Python):
  • reuse the existing tests before refactoring
  • add some more tests for convenient methods put into it's own componentUtil.ts file
  • add test to Skeleton.test.ts to check for passed height property
• E2E Tests
• Any manual testing needed?

---

Contribution License Agreement

By submitting this pull request you agree that all contributions to this project are made under the Apache 2.0 license.

[raethlein]

This change allows us to pass a height to the loading skeleton

[naterush]

@raethlein just opened an issue that I think deals with this PR here: #8285

Is it possible that this PR changed how heights are calculated for custom components inconsistently?