bots: Use /var/tmp for placing sink attachments to upload
bots: Use /var/tmp for placing sink attachments to upload

This becomes a problem before rebasing because the sink starts logging
long before we have a chance to rebase and get the bots
directory all setup and in place.

Besides this is cleaner.

Closes #6588
xhad/cockpit,larskarlitski/cockpit,andreasn/cockpit,petervo/cockpit,petervo/cockpit,stefwalter/cockpit,xhad/cockpit,michalskrivanek/cockpit,xhad/cockpit,cockpituous/cockpit,larskarlitski/cockpit,andreasn/cockpit,michalskrivanek/cockpit,harishanand95/cockpit,andreasn/cockpit,dperpeet/cockpit,deryni/cockpit,xhad/cockpit,dperpeet/cockpit,deryni/cockpit,SotolitoLabs/cockpit,martinpitt/cockpit,Scribery/cockpit,Scribery/cockpit,mareklibra/cockpit,michalskrivanek/cockpit,SotolitoLabs/cockpit,larsu/cockpit,mareklibra/cockpit,garrett/cockpit,larsu/cockpit,larskarlitski/cockpit,cockpit-project/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,larskarlitski/cockpit,deryni/cockpit,dperpeet/cockpit,deryni/cockpit,harishanand95/cockpit,stefwalter/cockpit,dperpeet/cockpit,SotolitoLabs/cockpit,garrett/cockpit,michalskrivanek/cockpit,garrett/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,mvollmer/cockpit,mareklibra/cockpit,Scribery/cockpit,deryni/cockpit,mareklibra/cockpit,michalskrivanek/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,harishanand95/cockpit,deryni/cockpit,andreasn/cockpit,larskarlitski/cockpit,petervo/cockpit,xhad/cockpit,moraleslazaro/cockpit,andreasn/cockpit,harishanand95/cockpit,Scribery/cockpit,larsu/cockpit,cockpituous/cockpit,stefwalter/cockpit,petervo/cockpit,harishanand95/cockpit,michalskrivanek/cockpit,martinpitt/cockpit,mvollmer/cockpit,harishanand95/cockpit,andreasn/cockpit,larsu/cockpit,cockpit-project/cockpit,larskarlitski/cockpit,michalskrivanek/cockpit,petervo/cockpit,xhad/cockpit,moraleslazaro/cockpit,dperpeet/cockpit,garrett/cockpit,mvollmer/cockpit,stefwalter/cockpit,garrett/cockpit,dperpeet/cockpit,mareklibra/cockpit,stefwalter/cockpit,martinpitt/cockpit,deryni/cockpit,Scribery/cockpit,mareklibra/cockpit,martinpitt/cockpit,dperpeet/cockpit,cockpit-project/cockpit,petervo/cockpit,SotolitoLabs/cockpit,mvollmer/cockpit,mareklibra/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,xhad/cockpit,Scribery/cockpit,cockpituous/cockpit,stefwalter/cockpit,moraleslazaro/cockpit,Scribery/cockpit,andreasn/cockpit,larskarlitski/cockpit,larsu/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,harishanand95/cockpit,petervo/cockpit,cockpituous/cockpit,stefwalter/cockpit,larsu/cockpit