add: accept-language to IncomingHttpHeaders (#34810)
add: accept-language to IncomingHttpHeaders (#34810)


borisyankov/DefinitelyTyped,mcliment/DefinitelyTyped,dsebastien/DefinitelyTyped,markogresak/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped