Use formik 'FastField' instead of 'Field' for performance reasons

On an Opencast system with a large number of series (>4,000), entering text in
the create or edit event dialogue box is slow. Using the formik 'FastField'
instead of 'Field' improves the performance.

Fixes #1406

Author: snoesberger

src/components/shared/Field.tsx

@@ -1,12 +1,12 @@
-import { Field as FormikField } from "formik";
+import { FastField as FormikFastField } from "formik";
 import { FieldAttributes } from "formik/dist/Field";
 
 /**
  * Wrapper for the Formik Fields
  */
 export const Field = (props: FieldAttributes<any>) => {
   return (
-    <FormikField
+    <FormikFastField
       {...props}
       onKeyDown={(event: KeyboardEvent) => {
         // Handler for basic html inputs to remove focus, if no custom component is passed