tests: move login after preparatory file operations in selenium_hwinfo test
tests: move login after preparatory file operations in selenium_hwinfo test

This test used to have this weird behavior, where cockpit.spawn got stuck,
trying to read the dmiinfo files for showing hwinfo.
Moving the file operations in the test before loading the page, seems to
solve this issue.

moraleslazaro/cockpit,moraleslazaro/cockpit,garrett/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,garrett/cockpit,deryni/cockpit,deryni/cockpit,mvollmer/cockpit,mvollmer/cockpit,martinpitt/cockpit,cockpituous/cockpit,cockpituous/cockpit,cockpituous/cockpit,cockpit-project/cockpit,deryni/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,garrett/cockpit,deryni/cockpit,garrett/cockpit,cockpituous/cockpit,deryni/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,cockpituous/cockpit,cockpit-project/cockpit,martinpitt/cockpit,deryni/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,garrett/cockpit,mvollmer/cockpit,deryni/cockpit,martinpitt/cockpit,martinpitt/cockpit