[skara] RFR: forge: add HostedRepository.webUrl for Branch

[Erik Helin]

Hi all,

please review this small patch that adds an overload for `webUrl` for a `Branch` on `HostedRepository`.

Thanks,
Erik

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Commit messages:
 - forge: add webUrl for Branch

Changes: https://git.openjdk.java.net/skara/pull/1027/files
 Webrev: https://webrevs.openjdk.java.net/?repo=skara&pr=1027&range=00
  Stats: 27 lines in 6 files changed: 27 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/skara/pull/1027.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/1027/head:pull/1027

PR: https://git.openjdk.java.net/skara/pull/1027