Use T.cleanup() to cleanup helm-action-test
Use T.cleanup() to cleanup helm-action-test

T.Cleanup() is introduced since go-1.14

Signed-off-by: Li Zhijian <77612007ee711fb02c065264d15511c027ff1ff7@cn.fujitsu.com>

adamreese/helm,adamreese/helm,bacongobbler/helm,helm/helm,helm/helm,bacongobbler/helm