fix(select): fix select-value label not filling select width

Author: rschmukler

src/components/select/select.scss

@@ -120,6 +120,7 @@ md-select {
 
   &.md-select-placeholder {
     display: flex;
+    flex-grow: 1;
     order: 1;
     pointer-events: none;
     -webkit-font-smoothing: antialiased;