Add new createTransaction method

frontend/src/app/Views/dashboard/dashboard.component.ts

@@ -45,8 +45,8 @@ const ELEMENT_DATA: PeriodicElement[] = [
 
 export interface TransactionData {
   symbol: string;
-  time: Date;
-  count: number;
+  time: string;
+  count: BigInt;
   price: number;
 }
 

frontend/src/app/Views/dashboard/user-dialog/user-dialog.component.ts

@@ -25,11 +25,17 @@ export class UserDialogComponent implements OnInit {
 
   onSubmit() {
     console.log(this.data);
-    this.dataService.createTransaction(
-      this.data.symbol,
-      this.data.time,
-      this.data.count,
-      this.data.price
+    console.log(
+      this.dataService
+        .createTransaction(
+          this.data.symbol,
+          this.data.time,
+          this.data.count,
+          this.data.price
+        )
+        .subscribe((data) => {
+          console.log(data);
+        })
     );
     this.dialog.closeAll();
   }