[#970] Slow git fetch with git+ssh protocol

Running git fetch on a cloned fusionforge git repo using the git+ssh procotol needs much time as shown below:

How to reproduce: $ cd ~ $ git clone $ git clone git+ssh://xxx@scm.fusionforge.org/scmrepos/git/fusionforge/fusionforge.git $ cd fusionforge $ time git fetch origin

real 0m26,050s user 0m0,014s sys 0m0,010s

$ time git fetch origin

real 0m26,021s user 0m0,022s sys 0m0,003s