Adding wizard and dialog footer loading spinner (#21230)

* Adding wizard and dialog loading

* Moving apis to proposed

* fixing namespace

* Only firing event when the value changes

* Only firing when value is changed

* Adding loading complete message to dialog and wizard

* Registering listeners and making a new base interface for loading components

* Fixing api comment

* Renaming prop to loadingCompleted

* old loading icon

src/sql/media/icons/loading.svg

@@ -4,7 +4,6 @@
     circle {
       animation: ball 0.6s linear infinite;
     }
-
     circle:nth-child(2) { animation-delay: 0.075s; }
     circle:nth-child(3) { animation-delay: 0.15s; }
     circle:nth-child(4) { animation-delay: 0.225s; }
@@ -12,7 +11,6 @@
     circle:nth-child(6) { animation-delay: 0.375s; }
     circle:nth-child(7) { animation-delay: 0.45s; }
     circle:nth-child(8) { animation-delay: 0.525s; }
-
     @keyframes ball {
       0% { opacity: 1; }
       100% { opacity: 0.3; }