fix(colors): change ionic colors scss imports for ionic dist (#29791)

Issue number: internal

---------

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## What is the current behavior?
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When consuming the Ionic Framework and using the Ionic Theme, the color
attribute was still not working as the color css was not present.

## What is the new behavior?
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this PR. -->

- Now the ion-color maps are correctly imported on the Ionic `dist`
related folder and not the on the `md/ios` ones.
- Changed the usage of `map.get` to `map-get` to avoid issues with the
usage of `@use` and `@forward`. This seems to have no impact on the
compilation and I believe its a better code convention, as map-gets are
a native scss function that doesn't need to be imported.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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  2. Update the BREAKING.md file with the breaking change.
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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: ionitron <hi@ionicframework.com>
Co-authored-by: Maria Hutt <maria@ionic.io>

core/scripts/testing/scripts.js

@@ -28,6 +28,27 @@
     document.head.appendChild(linkTag);
   }
 
+  /**
+  * The `ionic` theme uses a different stylesheet than the `iOS` and `md` themes.
+  * This is to ensure that the `ionic` theme is loaded when the `ionic:theme=ionic`
+  * or when the HTML tag has the `theme="ionic"` attribute. This is useful for
+  * the snapshot tests, where the `ionic` theme is not loaded by default.
+  */
+  const themeQuery = window.location.search.match(/ionic:theme=([a-z]+)/);
+  const themeAttr = document.documentElement.getAttribute('theme');
+
+  if ((themeQuery && themeQuery[1] === 'ionic') || themeAttr === 'ionic') {
+    const ionicThemeLinkTag = document.querySelector('link[href*="css/ionic/bundle.ionic.css"]');
+
+    if (!ionicThemeLinkTag) {
+      const linkTag = document.createElement('link');
+      linkTag.setAttribute('rel', 'stylesheet');
+      linkTag.setAttribute('type', 'text/css');
+      linkTag.setAttribute('href', '/css/ionic/bundle.ionic.css');
+      document.head.appendChild(linkTag);
+    }
+  }
+
   window.Ionic = window.Ionic || {};
   window.Ionic.config = window.Ionic.config || {};