Core: Duration ISO-8601 docs links not French (#21922)

I noticed that the links on https://docs.aws.amazon.com/cdk/api/v1/docs/@aws-cdk_core.Duration.html and https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.Duration.html took me to the French-language version the ISO site, https://www.iso.org/fr/standard/70907.html, which surprised me.

This changes that to remove `/fr` from the URL. (I haven't tested, but this might default to the right language for a user's browser, or always show English, but I think either of those are less surprising, given the rest of the CDK's docs are in English.)

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Author: plumdog

packages/@aws-cdk/core/lib/duration.ts

@@ -62,7 +62,7 @@ export class Duration {
   /**
    * Parse a period formatted according to the ISO 8601 standard
    *
-   * @see https://www.iso.org/fr/standard/70907.html
+   * @see https://www.iso.org/standard/70907.html
    * @param duration an ISO-formtted duration to be parsed.
    * @returns the parsed `Duration`.
    */
@@ -167,7 +167,7 @@ export class Duration {
    * Return an ISO 8601 representation of this period
    *
    * @returns a string starting with 'P' describing the period
-   * @see https://www.iso.org/fr/standard/70907.html
+   * @see https://www.iso.org/standard/70907.html
    */
   public toIsoString(): string {
     if (this.amount === 0) { return 'PT0S'; }
@@ -190,7 +190,7 @@ export class Duration {
    * Return an ISO 8601 representation of this period
    *
    * @returns a string starting with 'P' describing the period
-   * @see https://www.iso.org/fr/standard/70907.html
+   * @see https://www.iso.org/standard/70907.html
    * @deprecated Use `toIsoString()` instead.
    */
   public toISOString(): string {