Standardize button labels

lib/music_library_web/live/scrobble_rules_live/index.html.heex

@@ -14,7 +14,7 @@
             patch={~p"/scrobble-rules/new"}
           >
             <.icon name="hero-plus" class="icon" aria-hidden="true" data-slot="icon" />
-            {gettext("New Rule")}
+            {gettext("Add")}
           </.button>
           <.button
             variant="solid"
@@ -22,7 +22,7 @@
             phx-click="apply_all_rules"
           >
             <.icon name="hero-play" class="icon" />
-            {gettext("Apply All")}
+            {gettext("Apply")}
           </.button>
         </.button_group>
       </div>