Fix some issues reported by lintian

Fix some issues reported by lintian

• Use secure copyright file specification URI. (insecure-copyright-format-uri)

• Bump debhelper from old 12 to 13. (package-uses-old-debhelper-compat-version)

• Set upstream metadata fields: Bug-Database, Bug-Submit, Repository-Browse. (upstream-metadata-file-is-missing, upstream-metadata-missing-bug-tracking)

• Drop unnecessary dependency on dh-autoreconf.

• Update standards version to 4.6.1, no changes needed. (out-of-date-standards-version)

This merge proposal was created automatically by the Janitor bot. For more information, including instructions on how to disable these merge proposals, see https://janitor.debian.net/lintian-fixes.

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The bot will automatically update the merge proposal to resolve merge conflicts or close the merge proposal when all changes are applied through other means (e.g. cherry-picks). Updates may take several hours to propagate.

Build and test logs for this branch can be found at https://janitor.debian.net/lintian-fixes/pkg/s3backer/604080c8-99f3-4673-b9a3-335186de1a71.

Debdiff

These changes affect the binary packages:

[The following lists of changes regard files as different if they have different names, permissions or owners.]

Files in second set of .debs but not in first

-rw-r--r--  root/root   /usr/lib/debug/.build-id/42/4166854a2792cfb7b5ae52c876d7b12235e109.debug

Files in first set of .debs but not in second

-rw-r--r--  root/root   /usr/lib/debug/.build-id/87/a79cfd82ca40206ed1a8ac44292d1d79ddbb26.debug

No differences were encountered between the control files of package **s3backer**

Control files of package s3backer-dbgsym: lines which differ (wdiff format)

• Build-Ids: 87a79cfd82ca40206ed1a8ac44292d1d79ddbb26 424166854a2792cfb7b5ae52c876d7b12235e109

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