fix(segment-button): protect connectedCallback for when segment-content has not yet been created (#30133)

Issue number: internal

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## What is the current behavior?
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When the `connectedCallback` method is called for a segment-button and
its corresponding segment-content has not been created in that instant,
a console error is thrown and the method returns.

## What is the new behavior?
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this PR. -->
- `connectedCallback` will now wait, at most 1 second, for the
corresponding segment-content to be created.
- The new behaviour can be tested in segment-view/basic.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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## Other information

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