fix(progress-bar, spinner): update colors for ionic theme (#30418)

Issue number: internal

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## What is the current behavior?
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The colors were not working on progress bar when the theme was ionic; 
The Spinner with color="medium" should use the contrast variation by
design;

## What is the new behavior?
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this PR. -->
- Fix Progress-Bar Ionic Colors;
- Change Spinner Medium Color Variation;

## 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. -->

https://ionic-framework-git-rou-11917-ionic1.vercel.app/src/components/progress-bar/test/basic?ionic:theme=ionic

https://ionic-framework-git-rou-11917-ionic1.vercel.app/src/components/spinner/test/color?ionic:theme=ionic