Re-order frontend build steps

build.sh

@@ -400,19 +400,15 @@ then
     UploadTestArtifacts "net6.0"
 fi
 
-if [ "$LINT" = "YES" ];
+if [ "$FRONTEND" = "YES" ];
-then
-    if [ -z "$FRONTEND" ];
 then
     YarnInstall
-    fi
 
+    if [ "$LINT" = "YES" ];
+    then
         LintUI
     fi
 
-if [ "$FRONTEND" = "YES" ];
-then
-    YarnInstall
     RunWebpack
     UploadUIArtifacts
 fi