Initial draft of the begin component reference (#4272)

### What problem does this PR solve?

### Type of change


- [x] Documentation Update

web/src/pages/flow/form/begin-form/begin-dynamic-options.tsx

@@ -55,7 +55,7 @@ const BeginDynamicOptions = () => {
               icon={<PlusOutlined />}
               block
             >
-              Add field
+              Add option
             </Button>
             <Form.ErrorList errors={errors} />
           </Form.Item>