fix build links in input diff's, showed only current build in each link

Dependencies

• [2] 22JB5HNE make changes section more compact/readable
• [3] KAZWI5G4 * hydra: buildpage, show changes since last build/successful build
• [*] IK53RV4V

Change contents

• replacement in src/root/common.tt at line 282
  [2.1688]→[2.1688:1760](∅→∅)
  − <a href="[% c.uri_for('/build' build.id) %]">[% build.id %]</a>
  [2.1688]

  [3.1836]
  + <a href="[% c.uri_for('/build' input.dependency.id) %]">[% input.dependency.id %]</a>