message: fix(ts): add typing for content pseudobox property
diff: @@ -11,7 +11,9 @@ interface IPseudoBoxProps {
  * <PseudoBox _after={{content:`""` }}/>
  * ```
  */
  - _after?: BoxProps;
  + _after?: BoxProps & {
  + content: string;
  + };
  /**
  * Styles for CSS selector `&:before`
  *
  @@ -21,7 +23,9 @@ interface IPseudoBoxProps {
  * <PseudoBox _before={{content:`""` }}/>
  * ```
  */
  - _before?: BoxProps;
  + _before?: BoxProps & {
  + content: string;
  + };
  /**
  * Styles for CSS selector `&:focus`
  *
  