Integration tests break flags in go 1.13

[cvgw]

Actual behavior
Testing flags are overwritten by flags in integration_test.go

flag provided but not defined: -test.testlogfile

Expected behavior
Testing flags are not overwritten

To Reproduce
Steps to reproduce the behavior:

1. use golang 1.13
2. Execute a single integration test

Triage Notes for the Maintainers

Description	Yes/No
Please check if this a new feature you are proposing
Please check if the build works in docker but not in kaniko
Please check if this error is seen when you use --cache flag
Please check if your dockerfile is a multistage dockerfile