focus first input element in dialogs

pdb-js/src/app/dashboard-page/dashboard/add-plot-dialog/add-plot-dialog.component.ts

@@ -1,4 +1,4 @@
-import { Component } from '@angular/core';
+import { Component, ElementRef, ViewChild } from '@angular/core';
 import { MatDialogRef } from '@angular/material/dialog';
 
 @Component({
@@ -8,7 +8,6 @@ import { MatDialogRef } from '@angular/material/dialog';
 })
 export class AddPlotDialogComponent {
 
-
   constructor(public dialogRef: MatDialogRef<string>){
   }