Outline styles on direct descendant only

To reduce potential of style conflicts. (+2 squashed commits)
Squashed commits:
[4a3717f8da] Inherit a text color for outlined button, not forcing a specific one
[8b062a80bd] Do not apply text color if it is being overriden

Fixing #24625

packages/block-library/src/button/style.scss

@@ -73,7 +73,11 @@ $blocks-button__height: 3.1em;
 
 .is-style-outline > .wp-block-button__link,
 .wp-block-button__link.is-style-outline {
-	color: #32373c;
 	background-color: transparent;
 	border: 2px solid;
 }
+
+.is-style-outline > .wp-block-button__link:not(.has-text-color),
+.wp-block-button__link.is-style-outline:not(.has-text-color) {
+	color: #32373c;
+}