Update the options for the gen-l10n tool (#11046)

_Description of what this PR is changing or adding, and why:_

Adding `use-named-parameters` and `relax-syntax` to the list of options
for the `gen-l10n` command.

_Issues fixed by this PR (if any):_

None.

_PRs or commits this PR depends on (if any):_

None.

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---------

Co-authored-by: Shams Zakhour (ignore Sfshaza) <[email protected]>

src/content/ui/accessibility-and-internationalization/internationalization.md

@@ -844,7 +844,8 @@ at the command line or refer to the following table:
 | `[no-]format`                       | When specified, the `dart format` command is run after generating the localization files. |
 | `use-escaping`                      | Specifies whether to enable the use of single quotes as escaping syntax. |
 | `[no-]suppress-warnings`            | When specified, all warnings are suppressed. |
-| `use-named-parameters`              | Whether to use named parameters for the generated localization methods. |
+| `[no-]relax-syntax`                 | When specified, the syntax is relaxed so that the special character "{" is treated as a string if not followed by a valid placeholder and "}" is treated as a string if it doesn't close any previous "{" that is treated as a special character. |
+| `[no-]use-named-parameters`         | Whether to use named parameters for the generated localization methods. |
 
 {:.table .table-striped}