Cannot use with new version of RxJS (7.8.0 vs 5.5.12, for new Angular projects) #435

When trying to use this library you cannot use new RxJS operators, even simple ones like map.
Because the type of Observable does not match.

This forces many manual subscribes that could have been pipeline operators.

Minimal snippet (on new angular project with RxJS 7.8.0 and botframework-directlinejs 0.15.5):

return this.directLine.activity$.filter(x => x.type === 'message').pipe(map((x: Message): string => ''));

Possible solutions including making RxJS a peer dependency or upgrading it to a new version.