Move some partials around to more descriptive locations

scss/atat.scss

@@ -21,7 +21,7 @@
 @import 'components/empty_state';
 @import 'components/alerts';
 @import 'components/modal';
+@import 'components/footer';
+@import 'components/progress_menu.scss';
 
-@import 'sections/footer';
 @import 'sections/login';
-@import 'sections/progress_menu.scss';

scss/components/_footer.scss

@@ -1,4 +1,4 @@
-footer {
+.app-footer {
   background-color: $color-gray-lightest;
   border-top: 1px solid $color-gray-lighter;
   padding-left: $gap*4;