chore: remove deprecated attribute selectors (#28082)

Issue number: N/A

---------

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

The `text-wrap` attribute was removed in Ionic v5, but references to it
still exist in the `ion-label` stylesheets.


https://github.com/ionic-team/ionic-framework/blob/main/BREAKING_ARCHIVE/v5.md#css-utilities

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Removed references to the unsupported `text-wrap` attributed.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

Note: This is not a breaking change because support for `text-wrap` was
removed in Ionic v5.

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and migration path for existing applications below. -->


## Other information

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

core/src/components/label/label.ios.scss

@@ -4,8 +4,7 @@
 // iOS Label
 // --------------------------------------------------
 
-:host(.ion-text-wrap),
-:host([text-wrap]) {
+:host(.ion-text-wrap) {
   font-size: $label-ios-text-wrap-font-size;
 
   line-height: $label-ios-text-wrap-line-height;

core/src/components/label/label.md.scss

@@ -4,8 +4,7 @@
 // Material Design Label
 // --------------------------------------------------
 
-:host(.ion-text-wrap),
-:host([text-wrap]) {
+:host(.ion-text-wrap) {
   line-height: $label-md-text-wrap-line-height;
 }
 

core/src/components/label/label.scss

@@ -29,8 +29,7 @@
   color: current-color(base);
 }
 
-:host(.ion-text-wrap),
-:host([text-wrap]) {
+:host(.ion-text-wrap) {
   white-space: normal;
 }