Fix the xml path separator for ps4/5

[oxve]

b/288331664

[datadog-cobalt-youtube[bot]]

Datadog Report

Branch report: oxve-patch-1 Commit report: 0cb10f6

:white_check_mark: cobalt: 0 Failed, 0 New Flaky, 29550 Passed, 1 Skipped, 9m 48.15s Wall Time

[codecov[bot]]

Codecov Report

Merging #1868 (0cb10f6) into main (e7177db) will increase coverage by 0.02%. The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1868      +/-   ##
==========================================
+ Coverage   57.75%   57.77%   +0.02%     
==========================================
  Files        1915     1915              
  Lines       95111    95111              
==========================================
+ Hits        54931    54952      +21     
+ Misses      40180    40159      -21     

see 8 files with indirect coverage changes

[oxve]

The solution proposed here is not ideal. test_runner.py should be platform agnostic and use the launcher to deal with specifics.