Pixel and color tuning for ADB sideloading UI

From UX's feedback, the changes include:
 - Color link to Google Blue 600
 - Remove horizontal separator in Settings
 - Add space between policy indicator and the goggle

Test: visually looks good
Bug: chromium:893332
Change-Id: Ib24a44df02574301902012b6b480dc88a4b57f5e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1956067Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Commit-Queue: Victor Hsieh <victorhsieh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#722699}

chrome/browser/resources/chromeos/login/oobe_adb_sideloading_screen.html

@@ -7,6 +7,11 @@
     <link rel="stylesheet" href="chrome://resources/css/throbber.css">
     <link rel="stylesheet" href="oobe_dialog_host.css">
     <link rel="stylesheet" href="oobe_flex_layout.css">
+    <style>
+      a {
+        color: var(--google-blue-600);
+      }
+    </style>
 
     <!-- Dialog for normal confirmation -->
     <oobe-dialog id="enableAdbSideloadDialog" role="dialog" has-buttons

chrome/browser/resources/settings/crostini_page/crostini_arc_adb.html

@@ -11,11 +11,17 @@
 
 <dom-module id="settings-crostini-arc-adb">
   <template>
-    <style include="settings-shared"></style>
+    <style include="settings-shared">
+      cr-policy-indicator {
+        padding: 0 var(--cr-controlled-by-spacing);
+      }
+    </style>
     <div class="settings-box first">
-      <span>$i18n{crostiniArcAdbDescription}</span>
+      <div class="settings-box-text">
+        $i18n{crostiniArcAdbDescription}
+      </div>
     </div>
-    <div class="settings-box">
+    <div class="settings-box continuation">
       <div id="enableArcAdbLabel" class="start">
         $i18n{crostiniArcAdbLabel}
         <div class="secondary" hidden="[[!arcAdbNeedPowerwash_]]"