Aligns text elements on the navigation bar (#442)

* Aligns text elements on the navigation bar

* Moving variable to common variables file

* Moving variable to an already created group

amundsen_application/static/css/_variables-default.scss

@@ -91,6 +91,7 @@ $nav-bar-color: $indigo100;
 $nav-bar-height: 60px;
 $body-min-width: 1048px;
 $footer-height: 60px;
+$navbar-item-line-height: 36px;
 
 // SearchPanel
 $search-panel-width: 270px;

amundsen_application/static/js/components/NavBar/styles.scss

@@ -10,19 +10,22 @@
 
   .nav-bar-left {
     flex-basis: 234px;
+
     span.title-3 {
       color: $white;
+      line-height: $navbar-item-line-height;
     }
   }
 
   .nav-bar-right {
     margin-left: auto;
     display: flex;
+
     a {
       color: $white;
       display: inline-block;
       height: 100%;
-      line-height: 32px;
+      line-height: $navbar-item-line-height;
       padding: 0 8px;
 
       &.border-bottom-white:hover,