[hotfix][e2e] Cleaning logs before executing single tests.
[hotfix][e2e] Cleaning logs before executing single tests.

Logs of successful tests are cleaned up automatically. However, logs of
failing tests remain to ease debugging. However, if the developer does
not clean them before executing a new test with exception checks, the
new test will fail independent of the actual result as the old logs will
cause the checks to fail.

With this fix, failing tests will not cause subsequent tests to fail
because of parsing old logs.

twalthr/flink,lincoln-lil/flink,kl0u/flink,apache/flink,wwjiang007/flink,greghogan/flink,GJL/flink,gyfora/flink,darionyaphet/flink,lincoln-lil/flink,zjureel/flink,twalthr/flink,godfreyhe/flink,apache/flink,godfreyhe/flink,tillrohrmann/flink,tony810430/flink,zentol/flink,greghogan/flink,rmetzger/flink,darionyaphet/flink,aljoscha/flink,rmetzger/flink,gyfora/flink,GJL/flink,xccui/flink,tzulitai/flink,gyfora/flink,kaibozhou/flink,tzulitai/flink,gyfora/flink,bowenli86/flink,twalthr/flink,jinglining/flink,wwjiang007/flink,zentol/flink,jinglining/flink,jinglining/flink,StephanEwen/incubator-flink,tony810430/flink,hequn8128/flink,zjureel/flink,godfreyhe/flink,kl0u/flink,apache/flink,tony810430/flink,tillrohrmann/flink,GJL/flink,sunjincheng121/flink,tillrohrmann/flink,kl0u/flink,tony810430/flink,hequn8128/flink,wwjiang007/flink,tzulitai/flink,rmetzger/flink,xccui/flink,tillrohrmann/flink,clarkyzl/flink,darionyaphet/flink,bowenli86/flink,aljoscha/flink,zjureel/flink,godfreyhe/flink,tillrohrmann/flink,hequn8128/flink,tzulitai/flink,xccui/flink,hequn8128/flink,xccui/flink,bowenli86/flink,GJL/flink,zentol/flink,tony810430/flink,greghogan/flink,greghogan/flink,bowenli86/flink,wwjiang007/flink,xccui/flink,sunjincheng121/flink,clarkyzl/flink,zentol/flink,twalthr/flink,sunjincheng121/flink,rmetzger/flink,lincoln-lil/flink,StephanEwen/incubator-flink,aljoscha/flink,tillrohrmann/flink,kaibozhou/flink,zentol/flink,aljoscha/flink,rmetzger/flink,sunjincheng121/flink,greghogan/flink,jinglining/flink,lincoln-lil/flink,godfreyhe/flink,wwjiang007/flink,godfreyhe/flink,kaibozhou/flink,gyfora/flink,sunjincheng121/flink,sunjincheng121/flink,rmetzger/flink,bowenli86/flink,rmetzger/flink,godfreyhe/flink,kaibozhou/flink,aljoscha/flink,zjureel/flink,zjureel/flink,lincoln-lil/flink,twalthr/flink,clarkyzl/flink,wwjiang007/flink,StephanEwen/incubator-flink,hequn8128/flink,GJL/flink,darionyaphet/flink,hequn8128/flink,zjureel/flink,twalthr/flink,tzulitai/flink,aljoscha/flink,bowenli86/flink,gyfora/flink,greghogan/flink,darionyaphet/flink,GJL/flink,apache/flink,clarkyzl/flink,lincoln-lil/flink,twalthr/flink,gyfora/flink,kaibozhou/flink,zentol/flink,jinglining/flink,tony810430/flink,wwjiang007/flink,apache/flink,kaibozhou/flink,clarkyzl/flink,xccui/flink,jinglining/flink,tony810430/flink,StephanEwen/incubator-flink,kl0u/flink,zjureel/flink,xccui/flink,apache/flink,kl0u/flink,tzulitai/flink,zentol/flink,StephanEwen/incubator-flink,StephanEwen/incubator-flink,apache/flink,tillrohrmann/flink,lincoln-lil/flink,kl0u/flink