fix(tab-bar): ui tweaks for ionic theme (#30775)

Issue number: internal

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## What is the current behavior?
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The current UI of the tab-bar and tab-button in the ionic theme is not
matching the expected, in edge use cases:
- tab-button:
- Long label: causes the size of the tab-button to increase and
eventually making other tab-buttons, not visible.
- size: in different scenarios the size of each tab-button could become
different.
- tab-bar:
   - Many tab-buttons: would case some of them to become inaccessible.
   - Floating: distance from the bottom, was incorrect.

## What is the new behavior?
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this PR. -->
The changes made allow to fix the issues described above, specifically
for ionic theme, containing this way, potential impacts:
- tab-button:
   - min-width: has been defined for the tab-button.
   - property was set to force each tab-button to have the same size.
- tab-bar:
- allow the ability for the content to overflow on the x axis - a scroll
will appear if needed.
- increased the distance from the bottom, to comply with latest design
trends.

## Does this introduce a breaking change?
- [ ] Yes
- [x] No

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## Other information

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screenshots of how the component looks before and after the change. -->

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Co-authored-by: Brandy Smith <brandyscarney@users.noreply.github.com>