[fix] In routing proxy, match line beginning
[fix] In routing proxy, match line beginning

Previous approach failed in case of routing table like:

    {
      'domain.com': 'localhost:9000',
      'a.domain.com': 'localhost:9001'
    }

without `hostnameOnly`. When routing request to `a.domain.com`,
`RegExp` matched first entry (`domain.com`) and returned it.

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