DscpPolicyTest: fix linter errors

Test: TH
Bug: 235559605
Change-Id: I6501cd09b72734382fe05fd2227ad735cfc4fb15
Merged-In: I6501cd09b72734382fe05fd2227ad735cfc4fb15
(cherry picked from commit d02627df4dcbfff274780fac2b6ed53188ea7132)
1 file changed