fix(header): fix translate header

CHANGELOG.md

projects/ngx-dsfr-components/package.json

...b/components/header/demo/demo-header-focus.component.html

...lib/components/header/demo/demo-header-focus.component.ts

...omponents/src/lib/components/header/header.component.html

...-components/src/lib/components/header/header.component.ts

...nts/src/lib/components/translate/translate.component.html

...nents/src/lib/components/translate/translate.component.ts

...-dsfr-components/src/lib/shared/properties/messages.en.ts

...-dsfr-components/src/lib/shared/properties/messages.fr.ts