Fix link and language in feature request template
Fix link and language in feature request template

Resolves #3822

heartsucker/securedrop,ehartsuyker/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,conorsch/securedrop,ehartsuyker/securedrop,conorsch/securedrop,conorsch/securedrop,heartsucker/securedrop,heartsucker/securedrop,conorsch/securedrop,heartsucker/securedrop,conorsch/securedrop