gitlab: fix PATH for gitlab-exporter script

In prevision for gitlab-backup restore to be done in a script. In fact, it requires `sed` command to be available.
We have to add /bin to the PATH as `which sed` returns `/bin/sed`.

software/gitlab/instance-gitlab-export.cfg.in

@@ -28,7 +28,8 @@ pidfile       = ${gitlab-backup-directory:pid}/gitlab-exporter.pid
 environment   =
 # XXX: `/usr/bin` has to be in the PATH environment variable to be able to use
 # `which` command in gitlab-backup, `chrt` in xnice, ...
-  PATH=/usr/bin:${buildout:directory}/bin:{{ coreutils_location }}/bin:{{ grep_location }}/bin:{{ tar_location }}/bin:{{ gzip_location }}/bin:{{ gopath_bin }}:{{ git_location }}/bin
+# and `/bin` for `sed` command in gitlab-backup restore
+  PATH=/bin:/usr/bin:${buildout:directory}/bin:{{ coreutils_location }}/bin:{{ grep_location }}/bin:{{ tar_location }}/bin:{{ gzip_location }}/bin:{{ gopath_bin }}:{{ git_location }}/bin
 
 [cron-entry-gitlab-backup]
 <= cron-entry

software/gitlab/software.cfg

@@ -319,7 +319,7 @@ md5sum  = 89914e4a225f6cdebfa196d46359f6f2
 
 [instance-gitlab-export.cfg.in]
 <= download-file
-md5sum  = a295e524046a9e2af569ad4b55f210cd
+md5sum  = 00bd4ddf75a40a9d18d8243289f68ee9
 
 [macrolib.cfg.in]
 <= download-file