Remove $govuk-use-legacy-font code from components

src/govuk/components/back-link/_index.scss

@@ -34,18 +34,8 @@
 
     // Vertically align with the parent element
     position: absolute;
-
-    @if $govuk-use-legacy-font {
-      // Begin adjustments for font baseline offset
-      // These should be removed when legacy font support is dropped
-      $offset: govuk-em(1px, $font-size);
-      top: $offset * -1;
-      bottom: $offset;
-    } @else {
-      top: 0;
-      bottom: 0;
-    }
-
+    top: 0;
+    bottom: 0;
     left: govuk-em(3px, $font-size);
 
     width: $chevron-size;

src/govuk/components/breadcrumbs/_index.scss

@@ -54,17 +54,8 @@
       display: block;
 
       position: absolute;
-
-      @if $govuk-use-legacy-font {
-        // Begin adjustments for font baseline offset
-        // These should be removed when legacy font support is dropped
-        $offset: govuk-em(1px, $font-size);
-        top: $offset * -1;
-        bottom: $offset;
-      } @else {
-        top: 0;
-        bottom: 0;
-      }
+      top: 0;
+      bottom: 0;
 
       // Offset by the difference between the width of the non-rotated square
       // and its width when rotated

src/govuk/components/button/_index.scss

@@ -286,18 +286,4 @@ $govuk-button-text-colour: govuk-colour("white") !default;
     // (https://github.com/w3c/csswg-drafts/issues/6310)
     forced-color-adjust: auto;
   }
-
-  @if $govuk-use-legacy-font {
-    // Begin adjustments for font baseline offset when using v1 of nta
-    $offset: 2;
-
-    .govuk-button {
-      padding-top: (govuk-spacing(2) - $govuk-border-width-form-element - ($button-shadow-size / 2) + $offset); // s1
-      padding-bottom: (govuk-spacing(2) - $govuk-border-width-form-element - ($button-shadow-size / 2) - $offset + 1); // s1
-    }
-
-    .govuk-button__start-icon {
-      margin-top: -3px;
-    }
-  }
 }

src/govuk/components/header/_index.scss

@@ -322,25 +322,4 @@
       }
     }
   }
-
-  @if $govuk-use-legacy-font {
-    // Begin adjustments for font baseline offset
-    // These should be removed when the font is updated with the correct baseline
-    .govuk-header__logotype-crown,
-    .govuk-header__logotype-crown-fallback-image {
-      position: relative;
-      top: -4px;
-      vertical-align: middle;
-    }
-
-    .govuk-header {
-      $offset: 3px;
-      padding-top: $offset;
-    }
-
-    .govuk-header__link--homepage {
-      line-height: 30px;
-    }
-    // End adjustments
-  }
 }

src/govuk/components/tag/_index.scss

@@ -1,8 +1,14 @@
 @include govuk-exports("govuk/component/tag") {
   .govuk-tag {
+    @include govuk-font($size: 16, $weight: bold, $line-height: 1);
 
     display: inline-block;
 
+    padding-top: 5px;
+    padding-right: 8px;
+    padding-bottom: 4px;
+    padding-left: 8px;
+
     // When a user customises their colours often the background is removed,
     // by adding a outline we ensure that the tag component still keeps it's meaning.
     // https://accessibility.blog.gov.uk/2017/03/27/how-users-change-colours-on-websites/
@@ -15,23 +21,6 @@
 
     text-decoration: none;
     text-transform: uppercase;
-
-    @if $govuk-use-legacy-font {
-      // Since New Transport sits slightly higher than other common fonts.
-      // We use intentionally uneven padding to make it balanced, this can be
-      // removed using the version of the font that has a more common vertical spacing.
-      @include govuk-font($size: 16, $weight: bold, $line-height: 1.25);
-      padding-top: 4px;
-      padding-right: 8px;
-      padding-bottom: 1px;
-      padding-left: 8px;
-    } @else {
-      @include govuk-font($size: 16, $weight: bold, $line-height: 1);
-      padding-top: 5px;
-      padding-right: 8px;
-      padding-bottom: 4px;
-      padding-left: 8px;
-    }
   }
 
   .govuk-tag--grey {