[REF] event, web: BS5: $emphasized-link-hover-darken-percentage -> $link-shade-percentage

In BS5 `$emphasized-link-hover-darken-percentage` was removed, so we use
the new variable but we restore some BS4 values:

- 15% as in BS4
- remove the underline on links as in BS4

Task ID: 2766483

Part-of: odoo/odoo#95450

addons/event/static/src/scss/event.scss

@@ -55,7 +55,7 @@
     .o_list_button > .o_btn_cancel_registration {
         color: $danger;
         &:hover {
-            color: darken($danger, $emphasized-link-hover-darken-percentage);
+            color: darken($danger, $link-shade-percentage);
         }
     }
 }

addons/web/static/src/legacy/scss/bootstrap_overridden.scss

@@ -58,7 +58,9 @@ $body-color: $o-main-text-color !default;
 // Style anchor elements.
 
 $link-color: $o-main-link-color !default;
+$link-decoration: none !default;
 $link-hover-decoration: none !default;
+$link-shade-percentage: 15% !default;
 
 // Muted
 //

addons/web/static/src/legacy/scss/bootstrap_overridden_report.scss

@@ -1,2 +1,4 @@
+$link-decoration: none !default;
+
 // remove Emoji fonts
 $font-family-sans-serif: o-add-unicode-support-font(("Lucida Grande", Helvetica, Verdana, Arial, sans-serif), 1);

addons/web/static/src/legacy/scss/bs_mixins_overrides_backend.scss

@@ -22,7 +22,7 @@
 // It prioritizes the '$o-theme-text-colors' map and fallbacks to default.
 //------------------------------------------------------------------------------
 @mixin text-emphasis-variant($parent, $color) {
-  $-hover: $emphasized-link-hover-darken-percentage;
+  $-hover: $link-shade-percentage;
 
   // Check for the color name in '$theme-colors'.
   $color-name: null;

addons/web/static/src/libs/bootstrap/mixins_forwardport.scss

@@ -12,10 +12,10 @@
     #{$parent} {
         color: $color !important;
     }
-    @if $emphasized-link-hover-darken-percentage != 0 {
+    @if $link-shade-percentage != 0 {
         a#{$parent} {
             &:hover, &:focus {
-                color: darken($color, $emphasized-link-hover-darken-percentage) !important;
+                color: darken($color, $link-shade-percentage) !important;
             }
         }
     }