TT.t: fixup $_, since _ is a special variable, not a throwaway

Dependencies

• [2] LYRHVDS2 TT: add helpers for linking to jobs, jobsets, and projects, and for generating colon separated names.
• [3] ZY6CMDJY fixup: TT.t: move the :'s to the next line

Change contents

• replacement in t/View/TT.t at line 25
  [2.4895]→[2.4895:4926](∅→∅)
  − my($_, $c) = ctx_request('/');
  [2.4895]

  [2.4926]
  + my ($_request, $c) = ctx_request('/');