personal_settings: Restyle "Add a new bot" and "Add alert word" button.

This commit restyles the profile, account and privacy settings buttons
as follows:

- "Add a new bot": action-button-quiet-brand
- "Add alert word": action-button-quiet-brand

Fixes part of #33130.

web/templates/components/action_button.hbs

@@ -1,4 +1,4 @@
-<button type="button" class="{{#if custom_classes}}{{custom_classes}} {{/if}}action-button action-button-{{type}}-{{intent}}" {{#if data-tooltip-template-id}}data-tooltip-template-id="{{data-tooltip-template-id}}"{{/if}} tabindex="0" {{#if aria-label}}aria-label="{{aria-label}}"{{/if}}>
+<button type="button" {{#if id}}id="{{id}}"{{/if}} class="{{#if custom_classes}}{{custom_classes}} {{/if}}action-button action-button-{{type}}-{{intent}} {{#if hidden}}hide{{/if}}" {{#if data-tooltip-template-id}}data-tooltip-template-id="{{data-tooltip-template-id}}"{{/if}} tabindex="0" {{#if aria-label}}aria-label="{{aria-label}}"{{/if}}>
     {{#if icon}}
     <i class="zulip-icon zulip-icon-{{icon}}" aria-hidden="true"></i>
     {{/if}}

web/templates/settings/alert_word_settings.hbs

@@ -4,9 +4,12 @@
             {{t "Alert words allow you to be notified as if you were @-mentioned when certain words or phrases are used in Zulip. Alert words are not case sensitive."}}
         </p>
     </form>
-    <button class="button rounded sea-green" id="open-add-alert-word-modal" type="button">
-        {{t 'Add alert word'}}
-    </button>
+    {{> ../components/action_button
+      label=(t "Add alert word")
+      type="quiet"
+      intent="brand"
+      id="open-add-alert-word-modal"
+      }}
 
     <div class="settings_panel_list_header">
         <h3>{{t "Alert words"}}</h3>

web/templates/settings/bot_settings.hbs

@@ -11,7 +11,13 @@
         <div class="bot-settings-tip" id="personal-bot-settings-tip">
         </div>
         <div>
-            <button class="button rounded sea-green add-a-new-bot {{#unless can_create_new_bots}}hide{{/unless}}">{{t "Add a new bot" }}</button>
+            {{> ../components/action_button
+              label=(t "Add a new bot")
+              type="quiet"
+              intent="brand"
+              custom_classes="add-a-new-bot"
+              hidden=(not can_create_new_bots)
+              }}
         </div>
         {{/unless}}