docs: clarify CurrencyPipe display property (#25852)

Clarify how to suppress the currency/code in the CurrencyPipe by passing an empty string.

PR Close #25852

packages/common/src/pipes/number_pipe.ts

@@ -169,6 +169,7 @@ export class CurrencyPipe implements PipeTransform {
    * For example, the Canadian dollar CAD has the symbol `CA$` and the symbol-narrow `$`. If the
    * locale has no narrow symbol, uses the standard symbol for the locale.
    *   - String: Use the given string value instead of a code or a symbol.
+   * For example, an empty string will suppress the currency & symbol.
    *   - Boolean (marked deprecated in v5): `true` for symbol and false for `code`.
    *
    * @param digitsInfo Decimal representation options, specified by a string