feat(SplitButton): add flip prop support

src/SplitButton.tsx

@@ -19,6 +19,7 @@ export interface SplitButtonProps
  title: React.ReactNode;
  toggleLabel?: string;
  type?: ButtonType;
+ flip?: boolean;
 }
 
 const propTypes = {
@@ -74,6 +75,13 @@ const propTypes = {
  */
  rootCloseEvent: PropTypes.string,
 
+ /**
+ * Allow Dropdown to flip in case of an overlapping on the reference element. For more information refer to
+ * Popper.js's flip [docs](https://popper.js.org/docs/v2/modifiers/flip/).
+ *
+ */
+ flip: PropTypes.bool,
+
  /** @ignore */
  bsPrefix: PropTypes.string,
  /** @ignore */
@@ -114,6 +122,7 @@ const SplitButton = React.forwardRef<HTMLElement, SplitButtonProps>(
  menuRole,
  renderMenuOnMount,
  rootCloseEvent,
+ flip,
  ...props
  },
  ref,
@@ -146,6 +155,7 @@ const SplitButton = React.forwardRef<HTMLElement, SplitButtonProps>(
  role={menuRole}
  renderOnMount={renderMenuOnMount}
  rootCloseEvent={rootCloseEvent}
+ flip={flip}
  >
  {children}
  </Dropdown.Menu>